Apropas phenomenon of women predominance among carriers of reciprocal translocations during disturbances in reproduction

Resumo

The predominance of females among reciprocal (rec) translocation carriers, which have problems with reproduction in the anamnesis, is well established and usually accounts for the sterility of male carriers of this type of translocations. However, no careful comparative studies have been performed. Meta-analysis of the data on the examined pairs with reproduction problems shows that, among patients with infertility, the frequency of rec carriers was observed in 0.48% (74/15304) of men and in 0.41% (64/15454) of women; the sex ratio (SR) was 1.17, which does not differ significantly from the population value, 1.06 (p = 0.36). Robertsonian translocations (rob) were observed in 0.58% of men and in 0.11% of women; SR = 5.3 (p = 5 × 10^–13) in this group. Inversions (inv) were more often detected in women than in men, 0.14 and 0.27%, SR = 0.59 (p = 0.020). Among patients with habitual miscarriages, the frequencies of rec carriers were significantly higher than in patients with infertility: in 0.78% (151/19353) of men and in 1.42% (281/19737) of women, GR = 0.55 (p = 10^–9). Carriers of rob were found in 0.33% of men and 0.60% of women, SR = 0.55 (p = 9.7 × 10^–5). The frequency of inv was 0.17 and 0.20%, respectively. The results supports the notion that the predominance of women among fertile carriers of rob is caused by the sterility of male carriers of such rearrangements. However, the predominance of women among fertile carriers of rec cannot be due to this reason. The first reason is because there is no significant prevalence of men over women among infertile carriers of such type translocations. The second reason is because the frequency of rec male carriers among patients with infertility is significantly lower than their frequency among fertile carriers. It is likely that the reason for the observed phenomenon is the inherent oogenesis factors which affect segregation of the aberrant chromosomes.