[Multicentric study of Brazilian patients with 21-hydroxylase deficiency: a genotype-phenotype correlation].
We analyzed the clinical and molecular data of 205 patients with the three different clinical forms of 21-hydroxylase deficiency, in whom the clinical and molecular diagnosis were already defined. The most frequent mutations were I2 splice in the salt wasting form, I172N in the simple virilizing and V281L in the nonclassical form, presenting similar frequencies as those observed in other populations. We found a lower frequency of 21-hydroxylase gene deletion, similar to that previously identified in Argentinean and Mexican populations. Five new mutations were described in our population: G424S, H28+C, Ins 1003 1004 A, R408C and IVS2-2A>G. The genotype was classified in three groups according to the impairment of enzymatic activity observed in vitro, Group A: 0-2%, Group B: 3-7% and Group C: >20%. Group A mutations correlated with the salt wasting form, the Group B with simple virilizing form and Group C with the non classical form. The severity of genotype showed a positive correlation with higher 17OH-progesterone and testosterone levels. The I2 splice mutation in homo or hemizygosis confers classical form phenotype with both salt wasting and simple virilizing forms, precluding the prediction of the clinical form through genotype in pre and neonatal diagnosis. The good genotype-phenotype correlation in patients with 21-hydroxylase deficiency shows the usefulness of genotype to predict the clinical form for genetic counseling, prenatal diagnosis and to confirm neonatal screening diagnosis, except in cases with I2 splice mutation.
Bachega
Tânia A S S
TA
Departamento de Clínica Médica, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo. tbachega@usp.br
Billerbeck
Ana Elisa C
AE
Parente
Erica B
EB
Lemos-Marini
Sofia H V
SH
Baptista
Maria Tereza M
MT
Mello
Maricilda P
MP
Guerra
Gil
G
Kuperman
Hilton
H
Setian
Nuvarte
N
Damiani
Durval
D
Torres
Natália
N
Castro
Margaret de
Md
Mendonça
Berenice B de
BB
D000312:Adrenal Hyperplasia, Congenital / Q000235:genetics*; D002648:Child; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D009154:Mutation; D010641:Phenotype