At-haplotype (tw75) overlapping two complementation groups

Abstract

SUMMARYThe recessive lethal T/t-complex haplotypetw75was isolated from Jena, East Germany, prior to 1973. It was at first thought to be a standard member of thetw5complementation group because matings ofT/tw75×T/tw5produced tailless offspring only (Dunn, Bennett & Cookingham, 1973). Cross tests with all other complementation groups and embryological studies have recently been completed, with results demonstrating thattw75does not complement the members of either thetw5or thetw1complementation groups. Histological studies show that compound embryostw75/tw5andtw75/tw1die with symptoms indistinguishable fromtw5/tw5andtw1/tw1homozygtes respectively. Thustw75represents the first confirmed isolation of at-haplotype that overlaps two complementation groups.