Heritable genomic imprinting defects in infertile patients with oligozoospermia and azoospermia [Alteração transmissível do imprinting genómico em pacientes inférteis por oligozoospermia e azoospermia]

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Marques, CJ (Author) Other; Vaz, B (Author) Other; Costa, P (Author) Other; Sousa, S (Author) Other; carvalho, f (Author) FMUP; Fernandes, S (Author) Other; Silva, J (Author) Other; sousa, m (Author) ICBAS; barros, a (Author) FMUP

Journal

Title: Arquivos de Medicina

Vol. 21 No. 1

Pages: 41-45+67

ISSN: 0871-3413

Publisher: A E F M U P, Alameda prof. H. Montiero

Indexing

Scopus - 0 Citations

Other information

Authenticus ID: P-007-JTT

Abstract (EN): Introduction: We studied infertile patients with oligozoospermia and azoospermia to determine if these conditions of decreased sperm production are associated with defective genomic imprinting. Methods: We included 23 semen samples from men undergoing investigation of infertility as follows: 7 with normozoospermia (controls) and 16 with oligozoospermia (9 moderate; 7 severe); and 7 testicular biopsies, before intracytoplasmic sperm injection: 3 with conserved spermatogenesis (controls: 2 anejaculation, 1 secondary obstructive azoospermia) and 4 with hypospermatogenesis (HP). Sperm DNA was decondensed, purified and treated with sodium bisulfite. The differential methylated region (18 CpGs) of the H19 gene (paternally methylated) was amplified by PCR (Polymerase Chain Reaction), including the CTCF (parental-allele specific CCCTC-binding factor) binding site-6 that also controls the expression of IGF2 (Insulin-like Growth Factor 2) gene. PCR fragments were then cloned in plasmids and the methylation status of each cytosine was determined by automated sequencing. Results: We found a significant higher proportion of 1) global H19 hypomethylation in HP (p=0.001), 2) attainment of ¿3 CpGs in severe oligozoospermia and HP (p<0,001) and 3) of all 18 CpGs in HP (p<0,001). Regarding the CTCF binding site-6, we observed a significant higher proportion of 1) hypomethylation attaining ¿3 CpGs in HP (p<0,001) and 2) all 5 CpGs in HP (p<0,001). Conclusions: The establishment of genomic imprinting is defective in the male germ line of patients with severe oligozoospermia and hypospermatogenesis, being aggravated as the testicular injury worsens. ©ArquiMed, 2007.

Language: Portuguese

Type (Professor's evaluation): Scientific