A distortion of expected Mendelian ratios in a cross due to dysfunction or lethality in gametes bearing certain alleles. This form of meiotic drive (q.v.) is represented in Drosophila melanogaster by the segregation distorter (SD) mutation on chromosome 2. SD/sd + heterozygous males produce both SD and sd + spermatozoa, but only those carrying SD are functional. SD cannot achieve fixation, however, because it is lethal when homozygous.
Subjects: Genetics and Genomics.