Apparent mineralocorticoid excess syndrome in a Brazilian boy caused by the homozygous missense mutation p.R186C in the HSD11B2 gene.
The apparent mineralocorticoid excess syndrome (AME) is a rare autosomal recessive disorder due to the deficiency of 11beta-hydroxysteroid dehydrogenase type 2 enzyme (11beta-HSD2). The 11beta-HSD2 enzyme, encoded by HSD11B2 gene, metabolizes active cortisol in cortisone. Mutations on HSD11B2 gene affect the enzyme activity by leading to an excess of cortisol, which causes its inappropriate access to mineralocorticoid receptor. Therefore, cortisol will bind mineralocorticoid receptor. The human HSD11B2 gene maps to chromosome 16q22 and consists of five exons encoding a protein of 405 amino acids. We present here clinical and molecular studies on a Brazilian boy who was born pre-term after an oligodramnious pregnancy. He was diagnosed as having AME at the age of 26 months. His parents are second cousins. Molecular characterization of the HSD11B2 gene revealed the homozygous mutation p.R186C. The patient described here is the second case of HDS11B2 gene mutation reported in Brazilian patients with AME.
Coeli
Fernanda Borchers
FB
Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, SP, Brasil.
Ferraz
Lúcio Fábio Caldas
LF
Lemos-Marini
Sofia H V de
SH
Rigatto
Sumara Zuanazi Pinto
SZ
Belangero
Vera Maria Santoro
VM
de-Mello
Maricilda Palandi
MP
D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2 / Q000235:genetics*; D000595:Amino Acid Sequence; D002675:Child, Preschool; D003241:Consanguinity; D006720:Homozygote; D006801:Humans; D008297:Male; D043204:Mineralocorticoid Excess Syndrome, Apparent / Q000235:genetics*; D020125:Mutation, Missense / Q000235:genetics*
D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2