Y chromosome microdeletions and germinal mosaicism in infertile males.
Molecular deletions of the Y chromosome long arm are a frequent cause of male infertility. Because these deletions are thought to be inherited from fathers without Y chromosome deletions, the question arises as to whether their relatively high incidence in the male population could be due to the existence of a mosaicism in somatic and/or germinal paternal cells. This study included a total of 181 infertile men, among whom 18 were found to have an abnormal karyotype. In the other 163, polymerase chain reaction (PCR) analysis detected nine (5.5%) Y chromosome microdeletions. Blood, spermatozoa or testicular cells from 47 men (27 oligozoospermia, 20 azoospermia), including six Y-deleted patients, were screened for mosaicism using double target fluorescence in-situ hybridization (FISH) with Y centromeric and deleted in azoospermia (DAZ) gene-specific probes. Results indicated that: (i) percentages of double (intact Y chromosome) or single (deleted Y chromosome) fluorescent signals by FISH were in agreement with PCR data, thus demonstrating the reliability of the method; and (ii) a weak germ cell mosaicism was found in only two oligozoospermic patients, carrying 1.97 and 4.13% respectively of spermatozoa with a deleted Y chromosome. Further studies on larger populations are needed to evaluate precisely the incidence of Y deletion mosaicisms in infertile men.
Le Bourhis
C
C
Service d'Histologie, Biologie de la Reproduction et Cytogénétique et CECOS, Hôpital Tenon, 4 Rue de la Chine, 75020 Paris, France.
Siffroi
J P
JP
McElreavey
K
K
Dadoune
J P
JP
D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D000075364:Deleted in Azoospermia 1 Protein; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007248:Infertility, Male / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D009030:Mosaicism; D009845:Oligospermia / Q000235:genetics; D016133:Polymerase Chain Reaction; D016601:RNA-Binding Proteins / Q000235:genetics; D013094:Spermatozoa / Q000502:physiology; D013737:Testis / Q000502:physiology; D014998:Y Chromosome
C095668:DAZ1 protein, human; D000075364:Deleted in Azoospermia 1 Protein; D016601:RNA-Binding Proteins