Multiplex Ligation-Dependent Probe Amplification Analysis Is Useful for Diagnosing Congenital Adrenal Hyperplasia but Requires a Deep Knowledge of CYP21A2 Genetics

We read with great interest the recent report in Clinical Chemistry by Cantürk et al. (1). These authors affirmed that the CYP21A1P1 (cytochrome P450, family 21, subfamily A, polypeptide 1 pseudogene) genotype interferes with quantitative multiplex ligation-dependent probe amplification (MLPA) analysis of the CYP21A2 (cytochrome P450, family 21, subfamily A, polypeptide 2) gene. They also reported that the p.I172N and p.Q318X mutations were absent in 3.6% and 8.5%, respectively, of the CYP21A1P alleles (200 unrelated individuals examined)