Spermatogenic Failure 23

A number sign (#) is used with this entry because of evidence that spermatogenic failure-23 (SPGF23) is caused by homozygous mutation in the TEX14 gene (605792) on chromosome 17q23.

For a general phenotypic description and discussion of genetic heterogeneity of spermatogenic failure, see SPGF1 (258150).

Clinical Features

Gershoni et al. (2017) studied 2 infertile brothers from a consanguineous Iraqi Jewish family who had nonobstructive azoospermia. Testicular histology showed spermatogonia in all tubules, with only a few spermatocytes in some tubules.

Fakhro et al. (2018) reported 2 infertile Jordanian brothers who exhibited nonobstructive azoospermia, with no sperm in their semen. Testicular biopsy showed maturation arrest.

Molecular Genetics

In 2 infertile brothers with nonobstructive azoospermia from a consanguineous Iraqi Jewish family (family B), Gershoni et al. (2017) performed whole-genome sequencing and identified homozygosity for a 10-bp deletion in the TEX14 gene (605792.0001) that was not found in controls. Mutation status of unaffected family members was not reported.

In 8 Middle Eastern families in which at least 2 brothers had nonobstructive azoospermia (NOA), Fakhro et al. (2018) analyzed whole-exome sequencing data and identified 2 Jordanian brothers who were homozygous for a missense mutation in the TEX14 gene (R85L; 605792.0002). Their unaffected consanguineous parents were heterozygous for the mutation, and a fertile brother did not carry the mutation. Exome sequencing in 75 unrelated men with NOA revealed 2 additional men who were homozygous for TEX14 variants: a Nepalese man with Sertoli cell-only histology carried a frameshift variant, and a Tunisian man with Sertoli cell-only histology carried a splice site variant. Neither of those variants was found in 74 ethnically matched fertile men.