Disorders of spermatogenesis in carriers of balanced chromosome translocations

Introduction. Carriers of balanced chromosome translocations have an increased risk of gametogenesis and fertility disorders, aneuploidy in gametes and congenital malformations in offspring. Among men with infertility, the frequency of balanced translocations exceeds the general population, however, semen parameters, as well as the causes of spermatogenic disorders, are poorly studied in such patients.

Objective: to evaluate the effect of balanced chromosome translocations on spermatogenesis and semen parameters Methods. Male carriers of balanced chromosome translocations: Robertsonian (rob) (n=37) and autosome reciprocal translocations (n=38) were examined Standard semen analysis and quantitative karyological analysis of immature germ cells were performed.

Results. Semen disorders, varying from moderate to severe forms, were detected in 92% of carriers of autosome reciprocal translocations carriers and in 95% of rob carriers. In rob carriers oligoasthenoteratozoospermia (OAT) was the most common. Patients with OAT showed partial arrest of spermatogenesis in meiotic prophase I.

Conclusions. A difference in the structure of semen disorders was revealed in carriers of rob and reciprocal autosome translocations; oligozoospermia was the most common in patients with rob, indicating a partial arrest of spermatogenesis. Impaired fertility in male carriers of balanced autosome translocations with OAT is associated with a partial meiotic arrest, leading to decreased gamete production.

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