Meiotic errors in human oogenesis and spermatogenesis

• Published in: Reproductive biomedicine online Vol. 16; no. 4; pp. 523 - 531
• Main Author: Martin, Renée H
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 2008
• Subjects: aneuploidy; Chromosome Aberrations; Female; human chromosome abnormalities; human oogenesis; human spermatogenesis; Humans; Infertility, Male - genetics; Male; Maternal Age; meiosis; Meiosis - genetics; non-disjunction; Obstetrics and Gynecology; Oogenesis - genetics; Paternal Age; Recombination, Genetic; Spermatogenesis - genetics; aneuploidy; human oogenesis; human chromosome abnormalities; human spermatogenesis; non-disjunction; meiosis
• ISSN: 1472-6483; 1472-6491
• DOI: 10.1016/S1472-6483(10)60459-2

Abstract Chromosome anomalies are extraordinarily common in human gametes, with approximately 21% of oocytes and 9% of spermatozoa abnormal. The types of abnormalities are quite different since most abnormal oocytes are aneuploid, whereas the majority of abnormalities in spermatozoa are structural. Chromosomes 21 and 22 (the smallest chromosomes) are over-represented in aneuploid gametes in both oocytes and sperm. Chromosome 16 is also frequently observed in aneuploid oocytes, whereas the sex chromosomes are particularly predisposed to non-disjunction in human sperm. Maternal age is clearly the most significant factor in the aetiology of aneuploidy; theories about the cause of the maternal age effect are discussed. Paternal age does not have a dramatic effect on the frequency of aneuploid sperm; there is some evidence for a modest increase in the frequency of sex chromosomal aneuploidy. Meiotic recombination has a significant effect on the genesis of aneuploidy in both females and males. New techniques, which allow the analysis of recombination along the synaptonemal complex, have yielded interesting new information in healthy and infertile individuals. There is a link between infertility and the genesis of chromosome abnormalities. Future studies will unravel more of the underlying causal factors.