Carrier frequency of congenital adrenal hyperplasia (21-hydroxylase deficiency) in a middle European population.
Level 4 - case-series / case-control
Cross-sectional genetic prevalence study in an unselected cohort
PubMed 15572419 · doi:10.1210/jc.2004-1728
What was done
Researchers performed CYP21A2 genotyping using sequence and Southern blot analysis on 400 unrelated alleles from 200 clinically unaffected individuals in Austria (100 migrants from the former Yugoslavia and 100 individuals of non-Yugoslavian origin). Participants had no clinical hyperandrogenism and no family history of congenital adrenal hyperplasia (CAH).
What was found
The overall carrier frequency for CAH (CYP21A2 mutations) was 9.5%, including 5.5% classic and 4.0% nonclassic gene aberrations. The carrier rate was not significantly different between individuals of Yugoslav and non-Yugoslav origin (P = 0.8095).
Why it matters
This indicates that the true genetic carrier frequency for 21-hydroxylase deficiency in a middle European population is substantially higher than the 1:55 estimate derived from newborn screening data.
Limits
The sample size was modest (200 individuals, 100 per subgroup), limiting precision. Recruitment was limited to a single geographical area (Austria), which may not represent all European populations, and hormonal or clinical testing was not performed to correlate genotypes with endocrine status.
Cited by
- supports The carrier frequency for congenital adrenal hyperplasia genetic mutations is approximately 1 in 12.