Here I present: “Congenital Adrenal Hyperplasia”, Victor McKusick, Mendelian Inheritance in Man’, 1966. 先天性腎上腺增生。(CAH) icd10=E25.0
INTRODUCTION.
Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders characterized by impaired cortisol synthesis. It results from the deficiency of one of the five enzymes required for the synthesis of cortisol in the adrenal cortex. Most of these disorders involve excessive or deficient production of hormones such as glucocorticoids, mineralocorticoids, or sex steroids, and can alter development of primary or secondary sex characteristics in some affected infants, children, or adults. It is one of the most common autosomal recessive disorders in humans.
Congenital adrenal hyperplasia (CAH) results from a deficiency in one or another of the enzymes of cortisol biosynthesis. In about 95% of cases, 21-hydroxylation is impaired in the zona fasciculata of the adrenal cortex so that 17-hydroxyprogesterone (17-OHP) is not converted to 11-deoxycortisol. Because of defective cortisol synthesis, ACTH levels increase, resulting in overproduction and accumulation of cortisol precursors, particularly 17-OHP, proximal to the block. This causes excessive production of androgens, resulting in virilization.
There is evidence congenital adrenal hyperplasia is caused by homozygous or compound heterozygous mutation in the CYP21A2 gene encoding steroid 21-hydroxylase, on cytogenetic location 6p21.33 and genomic coordinates 6:32,038,415-32,041,644. The screenshot of the CYP21A2 gene 3,230 bp (base pairs) of DNA sequence length is shown BELOW. Nine (9) other genes besides CYP21A2 in the 6p21.33 cytogenetic location are listed BENEATH.
| Coordinate | Symbol | Genomic Name |
| 6:31,969,815 | DXO | Decapping exoribonuclease |
| 6:31,971,175 | STK19 | Serine/threonine protein kinase 19 |
| 6:31,982,057 | C4A | Complement component-4A |
| 6:32,014,795 | C4B | Complement component-4B |
| 6:32,038,415 | CYP21A2 | Cytochrome P450, subfamily XXIA, polypeptide 2 |
| 6:32,041,153 | TNXB | Tenascin XB |
| 6:32,115,264 | ATF6B | Activating transcription factor 6 beta |
| 6:32,128,707 | FKBPL | FK506-binding protein-like |
| 6:32,148,363 | PRRT1 | Proline-rich transmembrane protein 1 |
| 6:32,153,528 | PPT2 | Palmitoyl-protein thioesterase-2 |
