Cytogenetic Investigation in a Group of Ten Infertile Men with Non-Obstructive Azoospermia: First Algerian 46, XX Syndrome

Abstract

Background: In Algeria, the data on infertility and its various causes are rare. Recently, the introduction of assisted reproduction has allowed expecting that 300000 couples, which represent 7% of couples of reproductive age, face difficulty conceiving a child. Knowing that most idiopathic cases are likely to be due to chromosomal abnormalities, we aimed to investigate genetic defects by karyotype analysis in Algerian infertile men, using peripheral blood lymphocytes.

Methods: A cytogenetic study was conducted on 10 men from infertile couples by Karyotype analysis of R-banding performed by lymphocyte culture technique. Fluorescence in situ hybridization was performed and molecular abnormalities were investigated by polymerase chain reaction. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels were evaluated by immunoradiometric method.

Results: Chromosomal abnormalities were observed in 30% of the patients. We identified a homogenous Klinefelter syndrome patient with 47, XXY karyotype, a mosaic Klinefelter syndrome patient with 47, XXY/46, XY karyotype and a 46, XX male. Fluorescence in situ hybridization showed that the sex-determining region Y was translocated to the short arm of the X chromosome in patient with 46, XX chromosomal constitution and the presence of the SRY gene was confirmed by polymerase chain reaction and electrophoresis.

Conclusion: The occurrence of chromosomal abnormalities in 30% of the infertile men strongly supports the inclusion of routine cytogenetic testing for diagnostic establishment and suitable counseling for couples seeking for assisted reproduction technologies.

Keywords: Azoospermia; Cytogenetic; Male infertility; Severe oligozoospermia.

Fig. 1:

Constitutional karyotype of patient P3

Fig 2:

Constitutional karyotype of patient P9 with mitosis in 46, XY (a) and mitosis in 46, XXY (b)

Fig. 3:

Constitutional karyotype of patient P2

Fig. 4:

Fluorescence in situ hybridization (FISH) result. FISH analysis was performed on metaphase spreads of P2 and showed a copy of CEPX on each X chromosome and a copy of sex-determining region Y (SRY) on one chromosome X

Fig. 5:

Electrophoresis of the PCR products. Line 1: seize markers; line 2: SRY amplification of P2 (46, XX male); line 3: female control (46, XX); line 4: male control (46, XY); line 5: negative control