Human Disease Model Report: azoospermia, non-obstructive

General Information

Name

azoospermia, non-obstructive

FlyBase ID

FBhh0000533

Disease Ontology Term

azoospermia

Parent Disease

OMIM

Overview

Non-obstructive azoospermia or spermatogenic failure is defined as absence of any measurable level of sperm in semen, resulting from a defect in the production of spermatozoa in the testes. Approximately 10% of infertile men are diagnosed with non-obstructive azoospermia. There are approximately 20 genes that have been implicated in this condition (see the OMIM phenotypic series, link below); GWAS studies have identified additional candidate genes.

In humans, male infertility has been established as a risk factor for developing testicular cancer (reviewed in Maiolino et al., 2023; pubmed:37512119). Several Drosophila models also address this aspect of the disease.

[updated Jan. 2024 by FlyBase; FBrf0222196]

Disease Summary Information

Parent Disease Summary: azoospermia, non-obstructive

OMIM report

Symptoms and phenotype

Non-obstructive azoospermia (NOA), or failure of spermatogenesis within the testis, is diagnosed in approximately 10% of infertile men. NOA may be due to a lack of appropriate stimulation by gonadotropins, in which case hormonal therapy is usually effective. A larger category of non-obstructive azoospermia consists of men with an intrinsic testicular impairment. In these cases, the primary approach is to improve the quantity and quality of sperm retrieved from the testis for use for in vitro fertilization (Kumar, 2013; PMCID:PMC3583162).

(FlyBase Curators, 2013-)

Non-obstructive azoospermia (NOA) is defined as absence of any measurable level of sperm in semen, resulting from a defect in the production of spermatozoa in the testes. [from MedGen, Non-obstructive azoospermia; MedGen UID: 866757]

(FlyBase Curators, 2013-)

Genetics

Cellular phenotype and pathology

Spermatogenic arrest during meiosis is a cause of infertility. Meiotic arrest is characterized by germ cells that enter meiosis and undergo the first chromosomal reduction from 4n to 2n but are then unable to proceed further. This results in tubules containing spermatocytes as the latest developmental stage of germ cells. Meiotically arrested spermatocytes accumulate in the tubules, degenerate, and are easily distinguishable from normal spermatocytes by their partially condensed chromosomes (summary by Luetjens et al., 2004; pubmed:15070965). [from MIM:258150; 2025.03.08]

(OMIM, 2013-)

Molecular information

External links