A. Anand et Hs. Chandra, SYNERGISTIC INTERACTION BETWEEN PARTICULAR X-CHROMOSOME DELETIONS ANDSEX-LETHAL CAUSES FEMALE LETHALITY IN DROSOPHILA-MELANOGASTER, Journal of Genetics, 73(2-3), 1994, pp. 81-90
We studied the effect on female viability of trans-heterozygous combin
ations of X-chromosome deficiencies and Sxt-(fl), a null allele of Sex
-lethal. Twentyfive deficiencies, which together covered 80% of the X
chromosome, were tested. Seven of these trans-heterozygous combination
s caused significant levels of female lethality. Two of the seven inte
racting deficiencies include the previously known sex determination ge
nes sans fille and sisterless-a. Four of the remaining uncover X-chrom
osomal regions that were not hitherto known to contain sex determinati
on genes. These newly identified regions are defined by deficiencies D
f(1)RA2 (7D10; 8A4-5), Df(1)KA14 (7F1-2; 8C6), Df(1)C52 (8E; 9C-D) and
Df(1)N19 (17A1; 18A2). These four deficiencies were characterized fur
ther to determine whether it was the maternal or zygotic dosage that w
as primarily responsible for the observed lethality of female embryos,
daughterless and extra macrochaetae, two known regulators of Sxl, inf
luence the interaction of these deficiencies with Sxl.