4 research outputs found
Testicular Biopsies of Azoospermic Men at The Lagos State University Teaching Hospital
Objectives: This study was conducted to evaluate the histological findings from testicular biopsies in azoospermic men seen at the Lagos State University Teaching Hospital, Ikeja - Lagos, Nigeria.Patients and Methods: A retrospective study of testicular biopsies of azoospermic men who presented to our institution from 2005 to 2006 was performed. The patient’s age, type of infertility and histopathological diagnosis were evaluted. All biopsies were preserved in 10% formaldehydesolution.Results: Of the 51 azoospermic men (mean age 30 years, range 25 – 46 years) 25 (49.0%) had primary infertility, 11 (21.6%) had secondary infertility and 15 (29.0%) were not specified. Five (9.8%) patients had normal spermatogenesis. Abnormal histological parameters occurred in 46 (90.2%) patients: testicular atrophy in 30 (58.8%), maturation arrest in 14 (27.5%) and hypospermatogenesis in 2 (3.9%) patients.Conclusion: The presence of normal spermatogenesis in azoospermic men, which would suggest an obstructive lesion, is not common in our practice, in contrast to previous studies from our country. This may indicate a changing pattern in the aetiology of male infertility in our environment. Identification of the possible causes of testicular damage resulting in non-obstructive azoospermia in our environment may help to prevent male infertility.Key Words: Azoospermia, etiology, diagnosis, testicular biopsies, histopathology, infertility, environmen
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have
fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in
25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16
regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of
correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP,
while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in
Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium
(LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region.
Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant
enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the
refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa,
an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of
PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent
signals within the same regio
Multiple loci on 8q24 associated with prostate cancer susceptibility
Previous studies have identified multiple loci on 8q24 associated with prostate cancer risk. We performed a comprehensive analysis of SNP associations across 8q24 by genotyping tag SNPs in 5,504 prostate cancer cases and 5,834 controls. We confirmed associations at three previously reported loci and identified additional loci in two other linkage disequilibrium blocks (rs1006908: per-allele OR = 0.87, P = 7.9 x 10(-8); rs620861: OR = 0.90, P = 4.8 x 10(-8)). Eight SNPs in five linkage disequilibrium blocks were independently associated with prostate cancer susceptibility
Identification of seven new prostate cancer susceptibility loci through a genome-wide association study
Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. To identify common PrCa susceptibility alleles, we have previously conducted a genome-wide association study in which 541, 129 SNPs were genotyped in 1,854 PrCa cases with clinically detected disease and 1,894 controls. We have now evaluated promising associations in a second stage, in which we genotyped 43,671 SNPs in 3,650 PrCa cases and 3,940 controls, and a third stage, involving an additional 16,229 cases and 14,821 controls from 21 studies. In addition to previously identified loci, we identified a further seven new prostate cancer susceptibility loci on chromosomes 2, 4, 8, 11, and 22 (P=1.6×10−8 to P=2.7×10−33)