Linkage of an IDH locus with sex and two lethals in Aedes aegypti.

A previously unmapped isocitrate dehydrogenase (DH) locus has been mapped on chromosome 1 in Aedes aedes aegypti. No recombination between this and sex was observed in any of the several hundred instances where crossing over could have been detected. Within an isofemale line from Daker, two ldh-1 alleles are in linkage disequilibrium with two lethal loci. The two lethals complement one another, and show no recombination with sex or ldh-1. Recombination between bz and ldh-1 was demonstrated, placing ldh-1 very close to Me and sw. The results show that in two natural populations, ldh-1 and sex are in linkage disequilibrium with each other and most probably with the two lethal loci also. The distribution of ldh-1 variation world-wide and the implications of sex-linked lethals are discussed.