A rare CYP21A2 haplotype clarifies the phenotype-genotype discrepancy in an Italian patient with Non Classical Congenital Adrenal Hyperplasia (NC-CAH).

RCCX haplotypes with two copies of the CYP21A2 gene and one copy of the CYP21A1P pseudogene have been widely described in different populations. In most cases, the CYP21A2-like gene downstream of the TNXA gene showed a wild-type sequence or the c.293-13A/C > G variant while the CYP21A2 gene next to TNXB carried the p.(Gln319Ter) variant. Here is the discovery of a novel rare CYP21A2 haplotypes detected in an Italian patient with Non Classical Congenital Adrenal Hyperplasia (NC-CAH). The molecular family study was performed clarifying the previously found phenotype-genotype discrepancy.