title: [A genetic and hormonal study of 5 patients with the nonclassical form of congenital adrenal hyperplasia due to 21-hydroxylase deficiency].
abstract: BACKGROUND
  To study the association between the 21-hydroxylase deficiency with the HLA histocompatibility complex in a mediterranean ethnic group.
  
  
  METHODS
  5 patients with late-onset 21-hydroxylase deficiency, diagnosed on the basis of a high plasma level of 17-hydroxyprogesterone, along with 23 family members were typed. 17-hydroxyprogesterone response to iv ACTH stimulus was measured too in the family members.
  
  
  RESULTS
  We found a genetic linkage disequilibrium between the late-onset 21-hydroxylase deficiency and the HLA antigen B51. Moreover, similar biologic profiles were observed in the patients and those of their siblings who were HLA identical. The heterozygous carriers showed a intermediate 17-hydroxyprogesterone response to ACTH between propositus and homozygotes and their family members who had no HLA haplotype identical to those of the propositus.
  
  
  CONCLUSIONS
  These observations tend to confirm that a close linkage exits between the gene (or genes) for 21-hydroxylase deficiency in late-onset adrenal hyperplasia and the HLA genes. This association may change in the different ethnic groups.
authors.affiliation: Unidad de Endocrinología, Hospital General d'Alacant, Alicante.
authors.forename: F J
authors.initials: FJ
authors.lastname: Velasco
authors.forename: A M
authors.initials: AM
authors.lastname: Picó
authors.forename: C
authors.initials: C
authors.lastname: Muñoz
authors.forename: M
authors.initials: M
authors.lastname: Mauri
authors.forename: M L
authors.initials: ML
authors.lastname: de la Sen
mesh_terms: D019326:17-alpha-Hydroxyprogesterone; D000312:Adrenal Hyperplasia, Congenital / Q000097:blood / Q000453:epidemiology / Q000235:genetics*; D000324:Adrenocorticotropic Hormone; D016009:Chi-Square Distribution; D006580:Genetic Carrier Screening; D006680:HLA Antigens / Q000097:blood / Q000235:genetics; D006720:Homozygote; D006728:Hormones / Q000097:blood*; D006801:Humans; D006908:Hydroxyprogesterones / Q000097:blood; D010375:Pedigree; D011379:Prognosis
chemical_list: D006680:HLA Antigens; D006728:Hormones; D006908:Hydroxyprogesterones; D019326:17-alpha-Hydroxyprogesterone; D000324:Adrenocorticotropic Hormone
vernacular_title: Estudio genético y hormonal de 5 pacientes afectados de la forma no clásica de hiperplasia suprarrenal congénita por déficit de 21-hidroxilasa.