Background: Central precocious puberty (CPP) results from activation of the hypothalamic-pituitary-gonadal axis before the age of 8 years in girls and 9 years in boys. The molecular basis of the maturation of this axis is still poorly understood. The MRKN3 gene located in the Prader-Willi syndrome critical region (chromosome 15q11q13), inhibit factors stimulating pulsative. GnRH secretion. In 2013 inactivating mutations in the MRKN3 gene were discovered to cause some of the cases of familial precocious puberty. Subsequently, there have been few reports of apparently de novo mutations causing sporadic CPP.
Objective and hypotheses: The objective of the study was to investigate mutations in MKRN3 gene in patients with apparently sporadic idiopathic CPP.
Method: Blood samples were collected from 25 unrelated patients (24 girls and one boy), from two university medical centres. All patients were clinically diagnosed with precocious puberty of central origin. DNA was isolated from lymphocytes using standard procedures. The whole coding region of the MRKN3 gene was divided between five sets of primers. Each fragment was amplified with PCR, routinely cleaned and then sequenced with the classical Sangers method.
Results: No pathogenic variants of the MRKN3 gene were found among the studied group.
Conclusion: Although deficiency of MKRN3 causes CPP in humans, mutations in MRKN3 gene are a very rare genetic cause of isolated CPP.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology