English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We investigated whether molecular defects in the CYP21 gene were detectable in two common sex chromosome aberrations, the Turner and the Klinefelter syndromes. We found abnormal 17-hydroxyprogesterone levels after adrenal stimulation in 26/60 (43.3%) patients affected by these chromosome aberrations, as compared with only 11/68 (16.2%) normal controls (P=0.0014, odds ratio 4.0). Screening of the CYP21 gene identified a single Val281Leu missense mutation in exon 7 in 9/63 (14.3%) of the patients, all nine of whom were heterozygote carriers; the mutation frequency was significantly higher than in the general population (P=0.007, odds ratio=3.5). The hormonal and molecular data indicate that these common sex chromosome aberrations are associated with a remarkably high frequency of steroidogenic defects. It may be hypothesised that reduced levels of steroid 21-hydroxylase could confer a survival advantage, leading to a successful pregnancy.

Do reduced levels of steroid 21-hydroxylase confer a survival advantage in fetuses affected by sex chromosome aberrations?