RESUMO
Deletions of Y chromosome AZF locus were analyzed during a large-scale andrological and genetic examination of 810 infertile men. The search for Yq microdeletions was carried out according to the standard EAA/EMQN guidelines. The breakpoints were mapped for the deletions in AZF locus. The Y chromosome macro- and microdeletions were detected in 61 (7.5%) infertile men. The frequencies of AZF deletions during azoospermia and severe oligozoospermia amounted to 12.2 and 8.1 %, respectively. On the whole, the frequencies of Yq microdeletions and the genophenotypic correlations characteristic of various AZF deletion types comply with the relevant published data. However, spermatozoids in the ejaculate sediment of men with completely deleted AZFa region or AZFb+c deletions (from solitary spermatozoids to several dozens) were detected for the first time. It was demonstrated that the breakpoints were localized between AZFa and AZFb regions proximally to AZFb+c microdeletions for the majority of cytogenetically detectable deletions in the Y chromosome long arm. This indicates that the mechanisms underlying Yq macro- and microdeletions are somewhat different. The issues related to the role of Y chromosome deletions in the origins of monosomy for X chromosome and X/XY mosaicism are discussed.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Y/genética , Oligospermia/genética , Humanos , Infertilidade Masculina/genética , Masculino , Mapeamento Físico do CromossomoRESUMO
A comprehensive clinical, endocrinological, and medical genetic studies were made in 678 patients with reproductive disorders and infertility. A schedule was developed to examine the patients with successive current cytological, cytogenetic, molecular cytogenetics and molecular genetic methods. The pattern and proportion of chromosomal and genic abnormalities were defined among the total number of patients with reproductive disorders.