The sperm chromosomes of a man heterozygous for inv(20)(p13q11.2) were analyzed. Twenty-six sperm chromosome complements were examined, of which fourteen contained the normal chromosome, and twelve the inverted chromosome. None of the sperm complements contained a recombinant chromosome 20. The freq
Analysis of sperm chromosome complements from a man heterozygous for a pericentric inversion of chromosome 1
✍ Scribed by Renée H. Martin; Judy E. Chernos; R. Brian Lowry; H. Anthony Pattinson; Leona Barclay; Evelyn Ko
- Publisher
- Springer
- Year
- 1994
- Tongue
- English
- Weight
- 624 KB
- Volume
- 93
- Category
- Article
- ISSN
- 0340-6717
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✦ Synopsis
Human sperm chromosomes were studied in a man heterozygous for a pericentric inversion of chromosome (1)(p31q12). Q-banded pronuclear chromosomes were analyzed after in vitro penetration of golden hamster oocytes. A total of 159 sperm were examined: 54% bearing the inverted chromosome 1 and 46% the normal chromosome 1. These frequencies are not significantly different from the theoretical 1:1 ratio. There were no recombinant sperm with duplications or deficiencies, suggesting that a pairing loop failed to form or that crossing-over was suppressed. The frequency of abnormalities unrelated to the inversion was 5% for numerical, 8.8% for structural, 2.5% for numerical and structural, values not significantly different from control donors studied in our lab. The frequencies of X- and Y-bearing sperm were 46% and 54%, respectively, not significantly different from the expected value of 50%. This is the fifth pericentric inversion studied by human sperm chromosome analysis; recombinant chromosomes have been observed in two of the five cases. Some of the factors associated with an increased risk of recombinant sperm appear to be inversion size greater than 30% of the chromosome and chromosome breakpoints in G-light bands.
📜 SIMILAR VOLUMES
An inversion of chromosome 1 was found in three normal members of a two generation family. G- and C-banding studies revealed inv(1)(p13q23). The problems encountered in counseling such normal carriers are discussed.