Congenital adrenal hyperplasia is a hereditary disorder of steroidogenesis manifested by adrenal insufficiency and variable levels of hyper- or hypo-androgenism. The condition is mainly divided into two types: the classic form, which is characterised by severe enzyme deficiency and virilisation already in the prenatal phase, and the non-classic form, which has a mild enzyme deficiency and an onset of symptoms after birth.21-hydroxylase deficiency (21-OHD) is the most common variant of classic CAH. This is further subdivided into the simple virilising form, which affects approximately 25% of patients, and the salt-loss form, which affects 75% or more of individuals. In the latter case, aldosterone production is inadequate, exposing infants to the risk of life-threatening adrenal crisis. On the other hand, individuals affected by the non-classical form of 21-OHD show signs of postnatal hyperandrogenism and females do not show virilisation at birth.From a genetic point of view, 90-95% of CAH cases can be traced back to a mutation in the CYP21A2 gene, while mutations in the CYP11B1 gene constitute the second most frequent cause. As for epidemiological data, the estimated prevalence of the classical form is 1 in 10,000, with an annual incidence ranging between 1:5,000 and 1:15,000.
15 genes
1 to 3 out of 15000
Multi-gene panel aimed at the molecular diagnosis of non CYP21A2-related adrenogenital syndromes
Method: NGS sequencing, determination of SNVs (Single Nucleotide Variants), small insertions and deletions and CNVs (Copy Number Variants).
Limits: The test is unable to determine the presence of underrepresented somatic events, balanced chromosomal rearrangements, nucleotide expansion events of repeat regions, CNVs <3 contiguous exons. <3 esoni contigui.
Some genes may have low coverage areas, where necessary or upon specific request, within the limits of methodological limitations, sequencing can be completed with alternative methods (Sanger).
Some genes may be duplicated in the genome (pseudohgene), which may invalidate the analysis. The analysis cannot evaluate the CYP21A2 gene due to the presence of the pseudohgene. The analysis of this gene is performed separately by Sanger sequencing
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