saemia in a British hospital, with emphasis on heterozygote detection. Results are reported of a screening programme for galactosaemia covering a period of 2A years and 6415 births. The gene frequency for galactosaemia estimated from the data of the screening programme was 0-002. This conflicted with the known livebirth incidence of at least 1: 50,000 during this same period. 2 of the 4 galacto...

a cytogenetic study was performed on 11 tetraploid cotton cultivars (gossypium hirsutum l.)including the oltan cultivar and its crossing progenies. the chromosome pairing and chiasma frequency, aswell as meiotic abnormalities were compared among the genotypes studied. heterozygote translocations withalternate orientation were observed between some of the chromosomes of the a genome and those of...

Heterozygote advantage, or overdominance, remains a popular and persuasive explanation for the maintenance of genetic variation in natural populations in the face of selection. However, despite being first proposed more than 80 years ago, there remain few examples that fit the criteria for heterozygote advantage, all of which are associated with disease resistance and are maintained only in the...

cytes as a readily available source of this enzyme, its activity has been compared in 48 control subjects, seven homozygotes affected with homocystinuria, and 17 obligate heterozygotes. PHA-induced enzyme levels were highest in controls (mean ±SEM, 666.9±170.2 pmol cystathionine formed/mg protein per 4 h), intermediate in heterozygotes (114.4±27.3), and absent to severely deficient in homozygot...