Mutations of the KISS1 Gene in Disorders of Puberty

SILVEIRA LG; NOEL SD; SILVEIRA-NETO AP; ABREU AP; BRITO VN; SANTOS MG; BIANCO SDC; KUOHUNG W; XU S; GRYNGARTEN M; ESCOBAR ME; ARNHOLD IJ; MENDONCA BB; HAISER UB; LATRONICO AC

JOURNAL OF CLINICAL ENDOCRINOLOGY AND METABOLISM

ENDOCRINE SOC

Año: 2009

0021-972X

Mutations of the KISS1 Gene in Disorders of PubertyL. G. Silveira, S. D. Noel, A. P. Silveira-Neto, A. P. Abreu, V. N. Brito, M. G. Santos, S. D. C. Bianco, W. Kuohung, S. Xu, M. Gryngarten, M. E. Escobar, I. J. P. Arnhold, B. B. Mendonca, U. B. Kaiser1 and A. C. Latronico1 Unidade de Endocrinologia do Desenvolvimento (L.G.S., A.P.S.-N., A.P.A., V.N.B., M.G.S., I.J.P.A., B.B.M., A.C.L.), Laboratório de Hormônios e Genética Molecular LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP 05403-900 Brasil; Division of Endocrinology, Diabetes, and Hypertension (S.D.N., S.D.C.B., W.K., S.X., U.B.K.), Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts 02115; and Centro de Investigaciones Endocrinológicas (M.G., M.E.E.), División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, 1425 Buenos Aires, Argentina Address all correspondence and requests for reprints to: Leticia G. Silveira, M.D., or Ana C. Latronico, M.D., Hospital das Clinicas, Faculdade de Medicina da Universidade de Sao Paulo, Disciplina de Endocrinologia e Metabologia. Avenida Dr. Eneas de Carvalho Aguiar, 155, 2 degreeandar, Bloco 6, Sao Paulo, SP 05403-900, Brasil. E-mail: leticia_gontijo@yahoo.com.br or anacl@usp.br . Context: Kisspeptin, encoded by the KISS1 gene, is a key stimulatory factor of GnRH secretion and puberty onset. Inactivating mutations of its receptor (KISS1R) cause isolated hypogonadotropic hypogonadism (IHH). A unique KISS1R-activating mutation was described in central precocious puberty (CPP). Objective: Our objective was to investigate KISS1 mutations in patients with idiopathic CPP and normosmic IHH. Patients: Eighty-three children with CPP (77 girls) and 61 patients with IHH (40 men) were studied. The control group consisted of 200 individuals with normal pubertal development. Methods: The promoter region and the three exons of KISS1 were amplified and sequenced. Cells expressing KISS1R were stimulated with synthetic human wild-type or mutant kisspeptin-54 (kp54), and inositol phosphate accumulation was measured. In a second set of experiments, kp54 was preincubated in human serum before stimulation of the cells. Results: Two novel KISS1 missense mutations, p.P74S and p.H90D, were identified in three unrelated children with idiopathic CPP. Both mutations were absent in 400 control alleles. The p.P74S mutation was identified in the heterozygous state in a boy who developed CPP at 1 yr of age. The p.H90D mutation was identified in the homozygous state in two unrelated girls with CPP. In vitro studies revealed that the capacity of the P74S and H90D mutants to stimulate IP production was similar to the wild type. After preincubation of wild-type and mutant kp54 in human serum, the capacity to stimulate signal transduction was significantly greater for P74S compared with the wild type, suggesting that the p.P74S variant is more stable. Only polymorphisms were found in the IHH group. Conclusion: Two KISS1 mutations were identified in unrelated patients with idiopathic CPP. The p.P74S variant was associated with higher kisspeptin resistance to degradation in comparison with the wild type, suggesting a role for this mutation in the precocious puberty phenotype.