: Y DERIVATIVES The Y chromosome consists of a long arm (YL) and a short arm (YS); the long arm is arbitrarily taken as the left arm. Spe- cial Y chromosomes include (1) marked Y's which are used as Y tracers and (2) Y fragments, unmarked or marked, which are used as duplications or, when marked, as Y-arm tracers. Y fragments are symbolized either YL or YS plus necessary dis- tinguishing notation, e.g., YS8. The Y chromosome may be marked by mutating the genetically demonstrable elements of the Y or by translocating normal or mutant alleles from other parts of the complement to the Y chromosome. Marked-Y chromo- somes are symbolized by combining, without intervening punc- tuation, the symbol for the normal or mutant gene of primary marker intent with the symbol Y. If the marker is in the long arm, its symbol precedes Y (e.g., y+Y); if it is in the short arm, its symbol follows Y (e.g., Ybb). Symbols for marked fragments combine the symbol for the appropriate Y arm with that for the marker gene, listed in order. These notations are separated by a center point when the centromere lies between them (e.g. YL.scS1); otherwise they are not separated by punc- tuation (e.g., y+YL). The long arm of the Y carries a complex of male fertility genes, KL, plus an ABO element and Su(Ste), and the short arm carries a normal allele of bb and an ABO element proximally and a complex of male fertility factors, KS, distally. The genetic constitution of the Y chromosome may be designated by listing the above components and the cen- tromere in order from left to right, kl5+ kl3+ kl2+ ABO-YL Su(Ste) kl1+.ABO-YS bb+ ks1+ ks2+. The genetic constitution of a marker segment is designated by listing the symbols of the most widely separated loci known to be included in it separated by an em dash, e.g., bw+-ba+. The constitution of a Y fragment may be designated by listing its genetic elements in order with any ambiguities in order enclosed within parentheses, e.g., KL(bw+-ba+) bb+ KS. When there is a hierar- chy of ambiguities in order, a hierarchy of parentheses is used, as in ((ci+-spa+)KL)bb+KS. # 4Y constitution: ((ci+-spa+)KL)bb+KS; tentative. origin: X ray induced. synthesis: Edmondson, 1946. synonym: Tp4Y. references: Muller and Edmondson, 1957, DIS 31: 140-41. properties: Contains all known loci of chromosome 4 linked to the Y chromosome. Results from recombination between 4Y and YSX.YL suggest that 4 is inserted into or appended to YL. Two doses of this chromosome in the absence of any other Y- or 4- derived material produce viable and fertile flies of both sexes. #*BSw+y+Y constitution: BS pfd+ l(1)20Bb-su(f)+ PgdA-spl+ y+ ac+ KL.bb+ KS; inferred from origin. origin: X-ray-induced deletion of the majority of euchromatin (dm+ through mal+) from the recombinant composed of the left end of XPYD element of T(1;Y)148 = T(1;Y)2D;YL, which involves BSY, and the right end of XYL.YS129-16, which carries y+ from y+Y between X and YL. synthesis: Nicoletti. synonym: Dp(1;Y)BSw+y+. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. properties: Meiotic behavior and viability apparently normal. Produces Co effect; covers N. Has in addition combined marker characteristics of BSY and y+Y. # BSw+Y constitution: BS pfd+ l(1)20Bb-su(f)+ pn+-dm+ KL.bb+ KS; inferred from origin. origin: X-ray-induced deletion of the majority of euchromatin (rb+ through mal+) from a recombinant carrying left end of the XPYD element of T(1;Y)148 = T(1;Y)2D;YL, which involves BSY, and the right end of XYL.YS. synthesis: Nicoletti. synonym: Dp(1;Y)BSw+. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. properties: Produces Co phenotype in X/BSw+Y male and XX/BSw+Y female. Covers many N deficiencies. B phenotype as in BSY. # BSy+Y constitution: BS pdf+ l(1)20Bb+-su(f)+ y+ ac+ KL.bb+KS. origin: X-ray-induced deletion of the euchromatin (pn+ through mal+) from a recombinant carrying the left end of the XPYD element of T(1;Y)148 = T(1;Y)2D;YL, which involves BSY, and the right end of XYL.YS129-16, which carries y+ from y+Y between X and YL. synthesis: Nicoletti. synonym: Dp(1;Y)BSy+. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. Parker, 1968, DIS 43: 156. properties: Detachments from C(1)RM/BSy+Y females carry both markers (y+ and BS) or neither, so order not BSYy+ but BSy+Y as given. # BSY constitution: BS pdf+ l(1)20Bb+-su(f)+ KL.bb+KS. origin: X-ray-induced deletion of the euchromatin (including mal+) from a recombinant carrying the left end of the XPYD element of T(1;4)BS = T(1;4)15F9-16A1;16A7-B1;102F and the right end of XYL.YS. synthesis: Brosseau. synonym: YBS, Dp(1;Y)BS. references: Brosseau and Lindsley, 1958, DIS 32: 116. Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. properties: Causes extreme B phenotype; presence readily scor- able in +/+, B/+, and + but not in B or B/B constitutions. Shown to carry pdf+ in addition to B from 16A (Grell) and l(1)20Bb+ through su(f)+ from region 20 (Schalet and Lefevre, 1973, Chromosoma 44: 183-202). Does not cover spapol. Viabil- ity and fertility of X/BSY, X/BSY/BSY, and X/X/BSY good. Eyes of X/BSY detectably wider than those of X/BSY/BSY. Three euchromatic bands visible in salivary chromosomes (Nicoletti and Lindsley, 1960, Genetics 45: 1705-22). Prophase chromo- somes show the presence of an extra Hoechst-bright segment (BSXh) appended to the end of YL and separated from it by a non-fluorescent junction gap (BSXhj) (Gatti and Pimpinelli, 1983, Chromosoma 88: 349-73). # BSYbb- constitution: BS pdf+ l(1)20Bb+-su(f)+ KL.bb- KS; carries Ybb- deletion on YS. origin: Derived from original Ybb- chromosome of Schultz by recombination with BSYy+. synthesis: Komma. references: Endow, 1982, Genetics 102: 91-99. Hawley and Tartof, 1983, Genetics 104: 63-80. properties: Y chromosome deficient for most of the rDNA sequences, but carrying some sequences similar but not identi- cal to those on Ybb- chromosome (Endow, 1982). Marked with BS. Magnification induced as with Ybb-. # BSYy+ constitution: BS pdf+ l(1)20Bb+-su(f)+ KL.bb+KS ac+-l(1)1Aa+. origin: Recombination between BS and bw+Yy+. synthesis: Brosseau. references: Brosseau, 1958, DIS 32: 115-16. Brosseau, Nicoletti, Grell, and Lindsley 1961, Genetics 46: 339-46. Williamson, 1968, DIS 43: 157. properties: YL in mitotic prophase same as that in BSY; YS car- ries the Hoechst-bright segment (Xhy+) found on YL of y+Y (Gatti and Pimpinelli, 1983, Chromosoma 88: 349-73). other information: Several derivatives of BSYy+ with newly induced mutant alleles of y have been described. derivative origin ref ( phenotype ________________________________________________________________ BSYy61d tritium 1 yellowish body, bellow bristles, wild type wings BSYy67j EMS 3 yellow body, dark bristles BSYybl2 X ray 2 wild-type body, yellow bristles ( 1 = Hughes and Hildreth, 1967, DIS 42: 86; 2 = Seattle-LaJolla Drosophila Laboratories, 1971, DIS 47 (sup- plement); 3 = Williamson, 1968, DIS 43: 65. # BSYy31d constitution: BS pdf+ l(1)20Bb+-su(f)+ KL.bb+KS ac+ y31d- l(1)1Aa+; inferred from origin.. origin: Recombination between BSYy+ and In(1)sc8, y31d sc8 in a female. synonym: Dp(1;Y)BSy31d. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. # BS-Y: see y+Yv+ # BSVY origin: Five X-ray-induced derivatives of BSY. synthesis: Brosseau. synonym: Dp(1;Y)BSV. references: Brosseau, 1960, Genetics 45: 979. Moore, Procunier, Cross, and Grigliatti, 1979, Nature 282: 312-14. properties: Show variegation for B. With a normal X, the eye phenotype is B+, with XY, it is BS, and with XYL or XYS, it is intermediate B. The enhancers of variegation, Df(2R)M41A1 and E(var)7, shift the phenotype of BSVY flies toward normal (Brosseau, 1960), whereas deficiencies that wholly or par- tially remove His genes [Df(2L)TW65, Df(2L)TW84, and Df(2L)TW161] shift the phenotype toward BS (Moore et al.). other information: Eleven BSVYy+ chromosomes of independent origin (The Seattle-LaJolla Drosophila Laboratories, 1971, DIS 47, supplement) produce a larger eye phenotype in XY/Y males than in X/Y males. # bw+Y constitution: KL (bw+-ba+) bb+ KS. origin: Aneuploid segregant from Tp(2;Y)YL;58F1-59A2;60E3-F1 (Gersh, 1956, DIS 30: 115; Nicoletti). synthesis: Dempster. synonym: Y:bw+; Dp(2;Y)bw+. references: Muller, 1942, DIS 16: 64. 1951, DIS 25: 119. 1955, DIS 29: 146. properties: A section of 2R carrying bw+ inserted into YL prox- imal to KL (Baker, 1955, DIS 29: 101-03). Inserted segment known to carry normal alleles of bw, mr, or, Fo, Pin, bs, and ba but not px, hv, crs, M(2)58F, or M(2)60C. Males with two doses of bw+Y lethal. # bw+Yy+ constitution: KL (bw+-ba+) bb+ KS ac+-l(1)1Aa+ (Baker, 1955, DIS 29: 101-03). synthesis: Cooper. synonym: sc8Ybw+. references: Cooper, 1951, DIS 26: 97. # cn+Y constitution: Segment of 2R carrying cn+ inserted onto Y. origin: Dp(2;Y) segregant from Tp(2;Y)C = Tp(2;Y)41A;43. references: Sullivan, Kitos, and Sullivan, 1973, Genetics 75: 651-61. properties: Covers cn. # ct+y+Y constitution: KS cm+-ct + mal+-bb+ (het) y + ac + KL.KS (tenta- tive). origin: X-ray-induced deletion of the majority of the euchroma- tin from a recombinant carrying the left end of the XPYD ele- ment of T(1;Y)131 = T(1;y)6E;YS and the right end of XYL.YS129-16. synthesis: Johnson. synonym: Dp(1;Y)ct+y+. references: Johnson and Judd, 1979, Genetics 92: 485-502. Nicklas and Cline, 1983, Genetics 103: 617-31. properties: Carries wild-type alleles of y-ac, cm-ct, and mal- bb. # FR2: see y+YL # Fragment 2: see y+YL # l(1)1Ac+Y constitution: l(1)1Ac+ KL bb+ KS. origin: Neutron-induced derivative of y+Y. synthesis: Muller. synonym: l(1)J1+Y. references: Muller, 1954, DIS 28: 140-43. Padilla and Nash, 1977, Mol. Gen. Genet. 155: 171-77. properties: Like y+Y except that y+ and ac+, but not l(1)1Ac+ deleted; other l(1)1A loci not tested. # l(1)J1+Y: see l(1)1Ac+Y # pn-w+Y constitutioci: kz+-spl+ KL bb+ KS. # pn-w+Y origin: X-ray-induced loss of pn+ in w+Y chromosome. synthesis: Lifschytz and Falk. synonym: Dp(1;Y)pn-w+. references: Lifschytz and Falk, 1969, Genetics 62: 343-52. properties: Same as w+Y except for the absence of pn+. # R(Y)bw+ constitution: KL (bw+-ba+) bb+ KS; closed to form a ring. origin: X-ray-induced derivative of bw+Yy+. synonym: Ycbw+; MYR: Marked Y Ring. references: Oster and Lyengar, 1955, DIS 29: 159. Stone, 1982, Genetics 102: 245-58. properties: Ring shaped in mitotic metaphase. Lacks y+ present in the progenitor chromosome. Introduction of R(Y)bw+ via male into certain strains results in death of nearly all male pro- geny during early embryogenesis. About 10% of strains are sub- ject to such killing of male offspring. Introduction of R(Y)bw+ via female does not result in death of the sons (Oster, 1964, Genetics 50: 274). Inviability of R(Y)bw+- bearing embryos shown by Stone to depend on genotype of mother. # R(Y)F: Ring Y Filicidal constitution: Seven unmarked ring-Y chromosomes plus one marked with su(f)+. origin: X- and /-ray-induced derivatives of BSYy+. synthesis: Oster. references: Oster, 1964, Genetics 50: 274 (abstr.). Stone, 1982, Genetics 102: 245-58. properties: Pre-blastoderm embryos produced by so-called ring- sensitive females and carrying R(Y)F, either paternal or maternal in origin, are disorganized and fail to develop; the genetic basis of maternal ring sensitivity is complex (Stone). # R(YL) constitution: KL closed to form a ring. origin: Selected on the basis of marker loss from singly or doubly marked Y chromosomes; recovery from y+Y requires requires two breaks; those recovered from bw+Yy+ represent a rare subset of derivatives and are attributed to four breaks. chromosome origin source retains ref ( synonym __________________________________________________________ R(YL) spont y+Y KL 4 Ycl, YLc *R(YL)14 X ray bw+Yy+ KL 1, 3 YLc14 R(YL)15 spont bw+Yy+ KL 2, 3 YLc15 R(YL)16 X ray bw+Yy+ KL 1, 2 YLc16 R(YL)bb+ X ray bw+Yy+ KL bb+ 1, 3 YLc:bb+ ( 1 = Baker, 1955, DIS 29: 101-02; 2 = Baker, 1971, Proc. Nat. Acad. Sci. USA 68: 2472-76; 3 = Baker and Spofford, 1959, Univ. Texas Publ. 5914: 135-54 (fig.); 4 = Muller, 1948, DIS 22: 73-74. properties: R(YL) does not respond to the ring sensitivity of certain maternal genotypes (Oster, 1964, Genetics 50: 274). # R(YS)bw+ constitution: (bw+-ba+) bb+ KS; closed to form a ring. Order of elements inferred from origin. origin: X-ray-induced derivative of bw+Yy+. synthesis: W. K. Baker. synonym: YcS:bw+bb+. references: Baker and Spofford, 1959, Univ. Texas Publ. 5914: 135-54 (fig.). properties: Ring shaped in mitotic metaphase. Lacks y+ and KL from the treated chromosome. Shows some somatic and germinal instability. # RspYy+ constitution: M(2)41A+-l(2)41Aa+ KL bb+ KS ac+-l(1)1Aa+. origin: X-ray-induced deletion of majority of euchromatin from YP2RD element of T(Y;2)cb25, which has one break between BS and KL in BSYy+ and one proximal to Rsp in 2R; retained euchromatin not characterized. references: Lyttle and Ault, 1985, Genetics 110: s23. phenotype: Two such products isolated, 9 and 11. Both appear to show preferential recovery, with k values >0.95, among progeny of SD/+ males. other information: See also Tp(2;Y)Rsp. # sc.YL: see YL.scS1 # sc8ENc.o. Y: see YL.y+ # sc8.Y: see y+Y # sc8.Y:bw+: see bw+Yy+ # sc8V.Y: see yv56Y # scS1.YL#2: see YL.scS12 # scS1c.o.Y EY80: see YL.scS13 # scV1.YS constitution: l(1)1Aa+-scV1 bb+ KS; tentative. origin: Spontaneous recombinant from In(1)scV1/Y male. synthesis: Muller. references: 1948, DIS 22: 73-74. properties: Small, two-armed chromosome in mitotic metaphase. Survives in combination with C(1)DX and therefore carries bb+. # scV1.YS mwh+ constitution: l(1)1Aa+-scV1 bb+ KS ve+ mwh+. origin: Spontaneous derivative of Dp(1;1)scV1 and T(Y;3)P6 = T(Y:3)62A-B. synthesis: Ripoll and Garcia-Bellido. synonym: Dp(1;Y;3)H. references: 1973, DIS 50: 177. properties: Carries YS fertility factors plus mwh+ and ve+. y+ of the scV1 element variegates very strongly in y males; no mwh variegation. # shi+ Y origin: Deletions of the majority of the euchromatin from a recombinant comprising the left end of T(1;Y)P12 = T(1;Y)13F1-2;YSy+ and the right end of XYS.YLBS. synthesis: Poodry. synonym: Dp(1;Y)shi+. references: 1980, DIS 55: 210. properties: Covers sd, tc, and shi; marked with y+ and BS. chromosome constitution _____________________________________________________________________ shi+Y1 covers Df(1)sd72b = Df(1)13F1;14B1 only in the presence of Dp(1;4)r+ = Dp(1;4)14A1-2;16A1-2;102F2-3 *shi+Y2 shi+Y3 covers Df(1)sd72b, but not r at 15A1 # su(f)+Y origin: X ray induced in T(1;Y;4)BS males. synthesis: Wong, 1965. synonym: Dp(1;Y)su(f)+. references: Gethmann, 1967, DIS 42: 39. properties: Covers the deficiency in C(1)RA60g and carries su(f)+. # Tp4Y: see 4Y # TplY: see Dp(3;Y)Tpl # TplYtrxD: see Dp(3;Y)trxD # w+y+Y constitution: PgdA-Sgs4+ y+ ac+ KL.bb+ KS; inferred from origin and supposed constitution of BSw+y+Y. origin: X-ray-induced derivative of BSw+y+Y. synthesis: Nicoletti. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. properties: Like BSw+y+Y, but with BS and su(f)+ missing. # w+Y constitution: PgdA-Sgs4+ y+ KL.bb+ KS; inferred from origin. Dp(1;Y)2D1-2;3D3-4;Y (Judd et al.). Also Dp(1;Y)20B;20F according to Lifschytz and Yakobovitz. Also associated with T(Y;2)YL;22D (Schultz) in which the break in YL is distal to the PgdA-Sgs4+ insertion. origin: Spontaneous in C(1)RAYL/w+y+Y female. Seems likely that the progenitor w+y+Y was different from the one described here and was already translocated with chromosome 2. synthesis: Nicoletti. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. Judd, Shen, and Kaufman, 1972, Genetics 71: 139-56. Gerasimova and Ananjev, 1972, DIS 48: 93. Lifschytz and Yakobovitz, 1978, Mol. Gen. Genet. 161: 275-84. McGinnis, Farrell, and Beckendorf, 1980, Proc. Nat. Acad. Sci. USA 77: 7367-71. properties: Causes a confluens phenotype. molecular biology: 3D3-4 breakpoint lies between 1 and 2.5 kb to the right of the right breakpoint of Df(1)dm75e19 break- point (McGinnis et al.). # w+Y2 constitution: PgdA-Sgs4+ y+ KL.bb+ KS; inferred from origin. origin: /-ray-induced loss of y+ from w+y+Y. references: Kennison, 1981, Genetics 98: 529-48. properties: Like w+Y but not associated with a T(Y;2). # y+bbYbb- constitution: y+ bb KL bb- KS. origin: mei-41-induced exchange between BSYbb- and the distal heterochromatin of In(1)sc8, the BS marker on YL of BSYbb- being replaced by y+ bb from In(1)sc8. Site of exchange on the X within the rDNA; on the Y distal to kl5. references: Hawley and Tartof, 1985, Genetics 109: 691-700. properties: Male fertile with a normal X. # y+bb+Ybb- constitution: y+ bb+KL bb- KS. origin: Similar to that of y+bbYbb- except that the site of exchange on the X proximal to the rDNA. references: Hawley and Tartof, 1985, Genetics 109: 691-700. properties: Male fertile with a normal X. # y+bbrlYbb- constitution: y+bbrl KL.bb- KS. origin: Derived by reduction from y+bb+Ybb-. references: Hawley and Tartof, 1985, Genetics 109: 691-700. properties: Carries bbrl = reduced lethal, with about 20 rDNA genes. # y+dorY: see Dp(1;Y)dor # y+g+Y constitution: l(1)1Aa+-ac+ na+-ben+ KL bb+ KS. origin: X-ray-induced deletion of majority of euchromatin from XYL.YS, In(1)sc29 = In(1)1B;13A2-5. synthesis: Schalet. properties: Covers mus(1)101, ty, and g in addition to ben and na; should also carry Ste. Does not rescue Df(1)HA92 = Df(1)12A6-7;12D3; although some Df(1)HA92/y+g+Y males survive to late pupal stages, they are unable to complete emergence from the pupal case. # y+lz+Y constitution: l(1)1Aa+-ac+ lz+-mus109+ KL bb+ KS. origin: X-ray-induced deletion of majority of euchromatin from XYL.YS, In(1)yA74c = In(1)1B1-2;9D. synthesis: Schalet. properties: Does not cover t or Su(f). # y+na+Y constitution: l(1)1Aa+-ac+ na+ KL bb+ KS. origin: X-ray-induced deletion of majority of euchromatin from XYL.YS, In(1)sc29 = In(1)1B;13A2-5. synthesis: Schalet. properties: Covers na; neighboring genes not tested; should also carry Ste. Covers lethality of Df(1)RK2 = Df(1)12D2- E1;13A2-5, but surviving males are sterile and display an abnormal eye shape. # y+scY constitution: Dp(1;Y)1E3-4; Y arm involved not specified. synonym: Dp(1;Y)y+sc. references: White, Decelles, and Enlow, 1983, Genetics 104: 433-48. properties: Covers l(1)1Aa-su(wa). # y+Y constitution: l(1)1Aa+-ac+ KL.bb+ KS. origin: X ray induced in spermatogonial cell of In(1)sc8/Y male. synthesis: Muller. synonym: sc8Y. references: Muller, 1948, DIS 22: 73-74. Hadorn, Grell, and Schultz, 1970, Proc. Nat. Acad. Sci. USA 65: 633-37. Grell, R., 1971, Mol. Gen. Genet. 110: 218-37. Baker, 1973, Dev. Biol. 33: 429-40. properties: Tip of In(1)sc8 including l(1)1Aa+ through ac+, but not sc, transferred to the tip of YL distal to KL. YL appears to be as long as the X in metaphase (Hannah); a large Hoechst-bright segment (y+Xh) appended to the end of YL and separated from it by a short non-fluorescent gap (y+Xhj) (Gatti and Pimpinelli, 1983, Chromosoma 88: 349-73). Detach- ment studies show that bb+ from In(1)sc8 has not been transferred to YL (Parker). Has dominant Hw effect that pro- duces one or more humeral microchaetae in X/y+Y male and X/X/y+Y female and one or more hairs in the membrane of the second and third posterior cells of wing (Schultz) and extra veins, especially associated with the posterior crossveins (Williamson, 1968, DIS 43: 157) in X/y+Y/y+Y males. y/y+Y males show some variegation for y without enhancers of varie- gation and considerable y variegation in the presence of E(var)7 and E(var)21 (Hadorn et al., 1970; Grell, 1971). other information: Derivatives with mutant alleles of y have been recovered. derivative origin ref ( phenotype ________________________________________________ y53iY spont 2 yP59Y spont 3 like y2 yv56Y X ray 1 yellow variegation ( 1 = Hinton and Schmidt, 1956, DIS 30: 121; 2 = Luning, 1953, DIS 27: 58; 3 = Meyer, 1959, DIS 33: 97. # y+Ydor+ constitution: l(1)1Aa+-dor+ fog+-su(f)+ KS KL y+. origin: X-ray-induced deletion in X euchromatin of XYS.YL, y2 su(wa) wa KS . KL y+ male. synthesis: Holm. synonym: Dp(1;Y)dor+y+. references: Holm, 1968, DIS 43: 143. properties: Reduced body size and Hw effect in males. Body size normal and little Hw effect in compound-X-bearing females with the duplication. Duplication carries mutant alleles, y2 and su(wa) and a wild-type allele of y. # y+YL constitution: l(1)1Aa+-ac+ KL bb+. origin: Spontaneous product from YSX.YL, In(1)EN, KS y.KL y+ female. synthesis: Novitski. synonym: FR2: Fragment 2. references: Novitski, 1952, Genetics 37: 270-87. properties: Has subterminal centromere and extremely short second arm in mitotic metaphase. Constitution confirmed by analysis of detachments with C(1)RA, all of which appear to result from exchange between the interstitial heterochromatin of the compound and the bb+-bearing short arm of y+YL (Sandler, 1954, DIS 28: 153-54). # y+Ymal+1 constitution: l(1)1Aa+-ac+ KL.M(1)18C+-su(f)+ bb+ KS. origin: X-ray-induced euchromatic deletion in YSX.YL, In(1)EN, y.y+. references: Schalet, 1963, DIS 38: 82. # y+Ymal+2 constitution: l(1)1Aa+-ac+ KL.l(1)carot2+-su(f)+ bb+ KS. origin: Same as y+Ymal+1. references: Schalet, 1963, DIS 38: 82. other information: A number of X-ray-induced mal or mal- derivatives partially characterized in table below (Schalet and Finnerty, 1968, DIS 43: 65-66; Chovnick, Finnerty, Schalet, and Duck, 1969, Genetics 62: 145-60). derivative characterization ____________________________________________________ y+Ymal102 deficient for l(1)carot2-mal; retains l(1)19Ec+ y+Ymal106 noncomplementing mutation of mal y+Ymal107 deficient for l(1)carot2-eo y+Ymal108 deficient for l(1)carot2-unc; retains lfl+: breakpoint at 19E8-F1 (Schalet and Lefevre, 1973, Chromosoma 44: 183-200) y+Ymal113 deficient for sw-l(1)19Ec; retains ot+ to the left and unc+ to the right y+Ymal116 complementing mutation of mal y+Ymal118 deficient for mal-su(f); retains mel+ to the left y+Ymal126 deficient for l(1)carot2-l(1)19Ff; eo+ retained; breakpoint at 19F6-20A1 (Schalet and Lefevre) # y+Yv+ origin: Two X-ray-induced losses of BS from y+Yv+BS #1 (Chov- nick). synonym: BS-Y. # y+Yv+BS constitution: l(1)1Aa+-ac+ KL bb+ KS dy+-l(1)9Fe+ (KL?) su(f)+-l(1)20Bb pdf+ BS. origin: X-ray-induced deletion of the majority of the euchroma- tin from the recombinant carrying the left end of the XPYD element of T(1;Y)124 = T(1;Y)(9F;YL) and the right end of XYS.Yl110-8. synthesis: Chovnick. references: Chovnick, 1968, DIS 43: 170. properties: Three independent isolations; cover l(1)9Fe through v but not m according to Chovnick; #3, however, covers through dy but not fw (Schalet, 1969, DIS 44: 123). Lethal in combi- nation with Basc in males. # y+Yy+ constitution: l(1)1Aa+-ac+ KL bb+ KS ac+-l(1)1Aa+. origin: X ray induced. references: Parker and Busby, 1972, Mutat. Res. 16: 49-58. properties: Carries small duplication, marked with y+ and ac+, on the end of each arm. Flies with two y+Yy+ chromosomes show a pronounced Hw phenotype. # y2Y origin: X-ray- (Lefevre) or /-ray-induced (Gorelova) deletions of majority of euchromatin from XYL.YL, y2 su(wa) wa. synonym: Dp(1;Y)y2. chromosome synthesis ref ( cytology constitution _____________________________________________________________________ y2Y21T Gorelova 2, 3 2B6-8 l(1)1Aa+-y2-hfw KL.KS y2Y22T Gorelova 2 2B9-10 l(1)1Aa+-y2-fmf KL.KS y2Y40T Gorelova 2 2B9-11 l(1)1Aa+-y2-fmf KL.KS y2Y43T Gorelova 2 2E1-2 y2Y53T Gorelova 2, 3 2B6-8 l(1)1Aa+-y2-hfw KL.KS y2Y61l Lefevre 4, 6 1B14 y2Y67g19.1` Lefevre 1, 2, 3, 4, 5 2B17-18; l(1)1Aa+-y2-tlc ? KL.KS 23A3-4 y2Y67g24.2 Lefevre 1, 2, 3, 4 2B6-8;20F l(1)1Aa+-y2-hfw KL.KS ( 1 = Aizenzon and Belyaeva, 1982, DIS 58: 3-7; 2 = Belyaeva, Aizenzon, Kiss, Gorelova, Pak, Umbetova, Kramers, and Zhimulev, 1982, DIS 58: 184-90; 3 = Belyaeva, Aizen- zon, Semeshin, Kiss, Koczka, Baritcheva, Gorelova, and Zhimulev, 1980, Chromosoma, 81: 281-306; 4 = Craymer and Roy, 1980, DIS 55: 200-04; 5 = Hall and Kankel, 1976, Genetics 83: 517-35; 6 = White, Decelles, and Endow, 1983, Genetics 104: 433-38. # y59bY constitution: Carries l(1)1Aa+-sta; Y arm not specified; cyto- logically the Y carries 1A1-1B1-2. synthesis: Green. synonym: Dp(1;Y)y59b. references: Belyaeva, Aizenzon, Semeshin, Kiss, Koczka, Bar- itcheva, Gorelova, and Zhimulev, 1980, Chromosoma 81: 281- 306. Aizenzon and Belyaeva, 1982, DIS 58: 3-7 Belyaeva, Aizenzon, Kiss, Gorelova, Pak, Umbetova, Kramers, and Zhimulev, 1982, DIS 58: 184-90. properties: Covers l(1)1Aa-l(1)2Ad; partially covers sta (Aizenzon and Belyaeva, 1982). Marked with y59b, which resem- bles y1. # y66d constitution: YSYL.YS, KS bb+ y+ KL.bb+ KS (Williamson). origin: Spontaneous derivative of XYL.YS129-16. synthesis: Parker. references: Parker, 1968, DIS 43: 156. Williamson, 1973, DIS 50: 102. properties: Duplicated for KS and the nucleolus organizer, the two nucleoli being connected by YL. y sc/Y66d males are fer- tile and show more pronounced y variegation than XYL.YS129- 16/0 males. Y66d, like XYL.YS129-16, does not cover l(1)1Ac; it carries the y+ marker in an interstitial position (Parker, 1968). # YBS: see BSY # Ybb This is a group of Y chromosomes that carry insufficient numbers of ribosomal genes to produce wild-type bristle mor- phology. They are characterized by having 125 or fewer ribo- somal cistrons compared to 225 in wild-type Y chromosomess. Since numbers of ribosomal cistrons are unstable and subject to change by magnification or reduction, the estimates of cis- tron number presented here represent historical observations and need not reflect current compositions. The distinction between chromosomes designated Ybb- and those designated Ybb not always based on objective criteria; however, Ybb chromo- somes are generally hemizygous viable whereas Ybb- chromosomes are generally hemizygous lethal [e.g., in In(1)sc4Lsc8R/Ybb-] and therefore have few if any ribosomal cistrons. The original Ybb- was shown to have a foreshortened short arm; despite this cytological deficiency, however, derivative chromosomes with increased numbers of ribosomal genes have been recovered. Chromosomes designated in both ways are included in the fol- lowing table. chromosome origin discoverer ref ( phenotype rDNA gene # _________________________________________________________________________ Ybb spont Bridges, 1926 3 Ybb- Schultz, 33k8 3 YS one third normal length Ybb-1 | Ritossa 4, 7, 9 hemizygous lethal 100/0/10/ Ybb-2 | Ritossa 4, 7 hemizygous lethal 66` Ybb-3 | Ritossa 4,7 weak bb 125` Ybb-A1 | Atwood 2 hemizygous lethal Ybb-A2 | Atwood 2, 7 hemizygous lethal Ybb-S Spofford 2 hemizygous semi- lethal Ybb-Sdf Spofford 2 hemizygous lethal Ybb-T Tartof 11 hemizygous lethal 36- Ybbl spont Ritossa 1 hemizygous lethal YbbN2 spont? 7 weak allele ~100 YbbN3 spont 7 weak allele ~100 YbbP2 spont Tartof 5 moderate to 50% normal severe allele YbbRex n Rex- Robbins 8, 10 variable- induced strength exchange alleles Ybbrv 7 wild type >100 YbbSu(var) - 5, 7 severe allele 50 Ybbts1 6 mutant at 18 117 normal at 29 Ybbts2 6 mutant at 18 117 normal at 29 YbbX mei41 5 strong allele; induced Ybb+X derivative exchange Ybb+X mei41 5 normal allele; induced X derived in exchange two steps ( 1 = Atwood, 1969, Genetics 61: 319-27; 2 = Baker, 1971, Proc. Nat. Acad. Sci. USA 68: 2472-76; 3 = CP627; 4 = Endow, 1982, Genetics 102: 91-99; 5 = Hawley and Tartof, 1985, Genetics 109: 691-700; 6 = Procunier and Williamson, 1974, Dev. Biol. 39: 198-209; 7 = Ritossa, 1968, Proc. Nat. Acad. Sci. USA 59: 1124-31; 8 = Robbins, 1981, Genetics 99: 443-59; 9 = Spear, 1974, Chromosoma 48: 159-79; 10 = Swanson, 1987, Genetics 115: 271-76; 11 = Tartof, 1973, Genetics 73: 57-71. | Derived from the original Ybb-. / Estimated at 100 non-functional genes (Ritossa), no ribo- somal genes (Spear) and 10-12 ribosomal genes, some of them with type 2 repeats (Endow). ` Estimates of Ritossa. - Estimate of Tartof. Originally lethal with In(1)sc4Lsc8R, but phenotype can be changed to almost bb+ by magnification. n Regularly occurring product of Rex-induced mitotic exchange in progeny of crosses of Rex/+ or Rex/Rex females to YSX . YL/0 males; X/YbbRex males fertile. - Slight bb according to Hawley and Tartof, but strong bb according to Ritossa. Suppresses In(1)wm4 position-effect variegation. # YKpn constitution: Y carrying the tip of 3R, presumably YP3D element of a T(Y;3); Y arm not specified. origin: X ray induced. synthesis: Falk and Shamay. synonym: Dp(3;Y)awd+ [= Dp(3;Y)Kpn+]. references: Lifschytz and Falk, 1969, Genetics 62: 353-58. properties: Carries ca+ and Kpn+. # Ymal+ constitution: KL.sw+-su(f)+ bb+ KS; inferred from origin. origin: X-ray-induced deletion of majority of euchromatin [l(1)1Aa+-car+] from YSX.YL, In(1)EN. synthesis: E. H. Grell. references: Brosseau, Nicoletti, Grell, and Lindsley, 1961, Genetics 46: 339-46. other information: Two such chromosomes recovered, only one of which was kept. # Ycbw+: see R(Y)bw+ # Ycl: see R(YL) # YcL:bb+: see R(YL)bb+ # YcS:bw+bb+: see R(YS)bw+ # YL13 constitution: KL. origin: Spontaneous derivative of bw+Yy+. synthesis: W. K. Baker. references: Baker and Spofford, 1959, Univ. Texas Publ. 5914: 135-54. properties: A large acrocentric chromosome in mitotic meta- phase. Lacks y+, bw+, and KS present in the progenitor chromo- some. # YL.scS1 constitution: KL.bb+ scS1-l(1)1Aa+; presence of bb tentative. origin: Recombination between YS and distal heterochromatin of In(1)scS1. chromosome synonym ref ( cytology __________________________________________________________________________ YL . scS1 sc . YL 1, 4 submetacentric; shorter arm like YL YL . scS12 scS1 . YL#2 3 YL . scS13 scS1c.o.Y EY80 2 resembles Y ( 1 = Crew and Lamy, 1940, J. Genet. 39: 273-83; 2 = Linds- ley, 195; 3 = Parker and McCrone, 1958, Genetics 43: 172-86; 4 = Pontecorvo, 1940, DIS 13: 74. # YL.y+ constitution: KL.(bb+) ac+-l(1)1Aa+. origin: Spontaneous recombination between YS and the distal heterochromatin of In(1)sc8 in males. references: Lindsley, 1955, Genetics 40: 24-44. Ritossa, 1973, Proc. Nat. Acad. Sci. USA 70: 1950-54. properties: One of seven independent cases was deficient for bb (Lindsley). # YLc: see R(YL) # Yst: Y sterile constitution: KL.bb; in metaphases, the Y appears as a rod about the same length as YL. origin: Spontaneous; recovered in a we bbl female that was unexpectedly viable, bb, and fertile. synthesis: Bridges, 1926. references: CP552. properties: Males with Yst sterile in the absence of a YS or a normal Y. bbl/bbl/Yst females fertile and less extreme bb than bb/bbl females. # Ysu(f)- constitution: KL.l(1)20Ac+-sw+ bb+ KS. The Y carries at least one dose of bb+. origin: Spontaneous derivative of Ymal+. synonym: Dp(1;Y)su(f)-. references: Rahman and Lindsley, 1981, DIS 56: 108. properties: Deficient for uncl-su(f); carries sw+-l(1)20Ac+. # YS8 constitution: bb+ KS; tentative. origin: Spontaneous derivative of bw+Yy+ recovered from R(1)1/bw+Yy+ male. synthesis: W. K. Baker. synonym: YS:bb+-8. references: Baker and Spofford, 1959, Univ. Texas Publ. 5914: 135-54. properties: A small, two-armed chromosome in mitotic metaphase. Lacks y+, bw+, and KL present in the progenitor chromosome. # YSy+ constitution: bb+ KS ac+-l(1)1Aa+. origin: Derivatives of bw+Yy+. references: Baker, 1955, DIS 29: 101-12. Baker and Spofford, 1959, Univ. Texas Publ. 5914: 135-54 (fig.). derivative origin cytology _____________________________________________________________ YSy+5 spontaneous in large acrocentric R(1)/bw+Yy+ male YSy+6 X ray metacentric YSy+7 X ray acrocentric twice length of 4 # YS.YS constitution: KS bb+.bb+ KS. origin: Three independent cases; spontaneous; YS.YS2 and YS.YS3 arose in XYS/y+Y males. synonym: Y". properties: V-shaped chromosome in mitotic metaphase, with both arms the length of YS. chromosome discoverer ref ( _______________________________ YS . YS1 Stern 2 YS . YS2 Muller 1 YS . YS3 Muller 1 ( 1 = Muller, 1948, DIS 22: 73-74; 2 = Stern, 1929, Z. Indukt. Abstamm. Vererbungsl. 51: 253-353.