Reduced Testicular Steroidogenesis and Increased Semen Oxidative Stress in Male Partners as Novel Markers of Recurrent Miscarriage

BACKGROUND

Recurrent pregnancy loss, (RPL) affecting 1%–2% of couples, is defined as ≥3 consecutive pregnancy losses before 20-week' gestation. Women with RPL are routinely screened for etiological factors, but routine screening of male partners is not currently recommended. Recently it has been suggested that sperm quality is reduced in male partners of women with RPL, but the reasons underlying this lower quality are unclear. We hypothesized that these men may have underlying impairments of reproductive endocrine and metabolic function that cause reductions in sperm quality.

METHODS

After ethical approval, reproductive parameters were compared between healthy controls and male partners of women with RPL. Semen reactive oxygen species (ROS) were measured with a validated inhouse chemiluminescent assay. DNA fragmentation was measured with the validated Halosperm method.

RESULTS

Total sperm motility, progressive sperm motility, and normal morphology were all reduced in the RPL group vs controls. Mean ±SE morning serum testosterone (nmol/L) was 15% lower in RPL than in controls (controls, 19.0 ± 1.0; RPL, 16.0 ± 0.8; P < 0.05). Mean ±SE serum estradiol (pmol/L) was 16% lower in RPL than in controls (controls, 103.1 ± 5.7; RPL, 86.5 ± 3.4; P < 0.01). Serum luteinizing hormone and follicle-stimulating hormone were similar between groups. Mean ±SE ROS (RLU/sec/106 sperm) were 4-fold higher in RPL than in controls (controls, 2.0 ± 0.6; RPL, 9.1 ± 4.1; P < 0.01). Mean ±SE sperm DNA fragmentation (%) was 2-fold higher in RPL than in controls (controls, 7.3 ± 1.0; RPL, 16.4 ± 1.5; P < 0.0001).

CONCLUSIONS

Our data suggest that male partners of women with RPL have impaired reproductive endocrine function, increased levels of semen ROS, and sperm DNA fragmentation. Routine reproductive assessment of the male partners may be beneficial in RPL.

Detection of mutations in SF3B1, EIF1AX and GNAQ in primary orbital melanoma by candidate gene analysis

Background

Ocular melanoma is a rare but often deadly malignancy that arises in the uvea (commonest primary site), conjunctiva or the orbit. Primary orbital melanoma (POM) is exceedingly rare, with approximately 60 cases reported to date. Despite recent advances in our understanding of the genetics of primary uveal and conjunctival melanomas, this information is lacking for POM.

Methods

DNA was extracted from 12 POM tissues, with matched germline DNA (where available). MLPA was conducted to detect chromosomal alterations and Sanger sequencing used to identify point mutations in candidate melanoma driver genes (BRAF, NRAS, KRAS, GNA11, GNAQ), and other genes implicated in melanoma prognosis (EIF1AX, SF3B1). Immunohistochemistry was performed to analyse BAP1 nuclear expression.

Results

MLPA detected copy number alterations in chromosomes 1p, 3, 6 and 8. Sequencing of melanoma driver genes revealed GNAQ (p.Q209L) mutations in two samples; although it is possible that these samples represent extraocular spread of an occult uveal melanoma. A recurrent mutation in SF3B1 (p.R625H) was observed in indolent, but not aggressive, tumours; a mutation in EIF1AX (p.N4S) was detected in one patient with non-aggressive disease.

Conclusions

EIF1AX and SF3B1 mutations appear have a role in determining the clinical course of POM and detection of these changes could have clinical significance. Further in depth analysis of this rare group using differing ‘omic technologies will provide novel insights into tumour pathogenesis.

Gene of the month: PRPF31

Pre-mRNA splicing is an essential process in eukaryotic cells where the transcribed intronic sequences are removed, prior to translation into protein. PRPF31 is a ubiquitously expressed splicing factor, which aids in the assembly of the macromolecular spliceosome. Mutations in PRPF31 cause autosomal dominant retinitis pigmentosa (adRP), a form of retinal degeneration that causes progressive visual impairment. Interestingly, mutations in PRPF31 are non-penetrant, with some mutation carriers being phenotypically unaffected. In this review, the gene organisation, protein structure and biological function of PRPF31 are discussed, and the mechanisms of non-penetrance in PRPF31-associated adRP are discussed.