rs11805515 (CASZ1): Vaginal Bacteriome in Pregnancy

Key takeaways

• rs11805515, in the CASZ1 locus, appeared among 72 genome-wide significant hits in a genome-wide association study (GWAS) of vaginal bacterial traits in pregnant women
• The study enrolled 359 pregnant Chinese women and used 16S rRNA sequencing (a DNA marker method for identifying bacteria) to map vaginal bacterial communities
• Most significant variants in the study had low minor allele frequencies (MAFs, meaning they appear in a small fraction of the population); only 7 of the 72 exceeded an MAF of 0.05
• Interferon signaling was identified as a key pathway through which host genetics may influence vaginal bacterial communities during pregnancy
• This is a single study without reported independent replication, so the association at rs11805515 should be regarded as preliminary

What the research says A GWAS using 16S rRNA bacteriome analysis in 359 pregnant Chinese women found 72 associations between host genetic variants and vaginal bacterial traits (VBTs) at genome-wide significance (P < 5e-8), with a genomic inflation factor (lambda, a calibration statistic) below 1.1 indicating acceptable statistical reliability. The rs11805515 variant at the CASZ1 locus was among the genome-wide significant associations identified in this analysis. The study also characterized five vaginal community state types (CSTs) in the cohort, with CST-I (dominated by Lactobacillus crispatus, 37.3% of participants) and CST-IIIa (dominated by Lactobacillus iners, 29.8%) being the most common.

Reported associations

• Vaginal bacterial traits in pregnancy: rs11805515 was identified as a genome-wide significant association (P < 5e-8) with vaginal bacterial traits in a cohort of 359 pregnant Chinese women; the specific bacterial taxon or community measure linked to this variant was not detailed in the available study text
• Interferon signaling pathway enrichment (same study): Enrichment analyses across the 72 identified associations in the study suggested that genetic variants influencing interferon signaling may shape vaginal bacterial communities during pregnancy, though specific variant-pathway pairings for rs11805515 were not described in the provided text

Evidence quality The evidence for rs11805515 comes from a single GWAS of 359 pregnant Chinese women, a modest sample size by GWAS standards (large GWAS typically involve tens of thousands of participants). The genomic inflation factor (lambda) below 1.1 indicates the statistical approach was well-calibrated, reducing the likelihood of systematic false positives. All 72 associations, including the one at rs11805515, reached the conventional genome-wide significance threshold (P < 5e-8). The majority of significant variants had low MAFs, which can reduce the stability of effect estimates in smaller samples. No independent replication of the 72 associations was reported in the study. Specific p-values and effect sizes for rs11805515 were not available in the study text provided. The cohort consisted of pregnant Chinese women, so findings may not generalize to other ethnicities or to non-pregnant populations.

Lifestyle considerations No lifestyle considerations on file for this variant.