Sperm chromosome analysis in a man heterozygous for a reciprocal translocation 46,XY t(12;20)(q24.3;q11).
Sperm chromosome complements were studied in a man who carried a reciprocal translocation t(12;20)(q24.3;q11). A total of 113 spermatozoa were karyotyped after in-vitro penetration of hamster eggs. 2:2 and 3:1 meiotic segregations were observed with the following frequencies: alternate 47%, adjacent 1 42%, adjacent 2 10%, 3:1 2%. For alternate segregations, the number of normal spermatozoa (25) was not significantly different from the number of spermatozoa carrying a balanced form of the translocation (28), as theoretically expected. The proportion of spermatozoa with an unbalanced form of the translocation was 53%. There was no evidence for an interchromosomal effect since the frequencies of numerical and structural abnormalities (unrelated to the translocation) were within the normal range of control donors.
Department of Paediatrics, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
R H
RH
Martin
B
B
McGillivray
L
L
Barclay
K
K
Hildebrand
E
E
Ko
D000328:Adult; D002881:Chromosomes, Human, Pair 12; D002890:Chromosomes, Human, Pair 20; D006579:Heterozygote; D006801:Humans; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D010375:Pedigree; D013094:Spermatozoa / Q000648:ultrastructure*; D014178:Translocation, Genetic