NONCHROMOSOMAL INHERITANCE
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sigma: carbon dioxide sensitivity
 origin: Spontaneous.
 discoverer: L'Heritier and Teissier, 1937.
 references: 1937, Comp. Rend. 205: 1099-1101.
  1938, Comp. Rent. 206: 1193-96, 1683.
  1945, Publ. Lab. Ecole Norm. Super. Biol. (Paris) 1: 35-74.
  L'Heritier, 1948, Heredity 2: 325-48.
  1951, Cold Spring Harbor Symp. Quant. Biol. 16: 99-112.
  1958, In Advances in Virus Research, Vol. 5 (K. M. Smith
  and M. A. Lauffer, eds). Academic Press,
  Inc., pp. 195-245.
  L'Heritier and Plus, 1963, In Biological Organization
  at the Cellular and Supercellular Level
  (R. J. C. Harris, ed.). Academic Press Inc., pp. 59-71.
 phenotype: Flies anesthetized with carbon dioxide are paralyzed
  and die, whereas normal flies recover in a short
  time. The cause of carbon dioxide sensitivity is a
  virus or virus-like particle whose diameter is 180 microns,
  as estimated from filtration experiments and 45 microns from X-ray target 
  experiments. Carbon
  dioxide-sensitive strains may be divided into two
  types: stabilized and nonstabilized. Artificial
  inoculation regularly leads to nonstabilized
  condition. In this state, males do not transmit
  sensitivity to progeny, and females do transmit it to
  a part of their progeny. Some flies of a
  nonstabilized strain achieve the stabilized state.
  Flies in the stabilized state yield only one-fifth as
  many infectious units as nonstabilized flies;
  however, all progeny of stabilized females are
  sensitive, as are part of the progeny of stabilized
  males. Progeny of stabilized females are also
  stabilized. In contrast, the sensitive progeny of
  stabilized males are nonstabilized. Several viral
  mutations that affect transmisson or replication have
  been studied; the D. melanogaster mutant,
  ref, inhibits multiplication of most viral
  strains.
#
SR: Sex Ratio
 origin: Artificially inoculated into D. melanogaster
  from SR-bearing D. willistoni or
  D. nebulosa.
 references: Poulson and Sakaguchi, 1961, Genetics 46: 890-91.
  Sakaguchi and Poulson, 1962, Ann. Rep. Natl. Inst. Genetics
  (Misima, Japan) 12: 18-19; 19-21.
  1963, Genetics 48: 841-61.
  Poulson, 1963, In Methodology in Basic Genetics
  (W. J. Burdette, ed.). Holden-Day Inc., pp. 404-24.
 phenotype: Females with SR produce few or no male progeny;
  SR is transmitted only from mothers to
  daughters. The SR agent is infective and may
  be established from artificial inocula. The
  SR condition is always associated with
  presence of small treponema-like spirochetes in
  hemolymph of affected females. Degree of stability
  of the infection differs among D. melanogaster
  strains. Male dies as embryo.
  Triploid intersexes not killed by SR nor are
  transformed females (X/X; tra/tra).
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