A missense mutation in MKRN3 in a Danish girl with central precocious puberty and her brother with early puberty.
BACKGROUND
Idiopathic central precocious puberty (ICPP) results from the premature reactivation of the hypothalamic-pituitary-gonadal axis leading to development of secondary sexual characteristics prior to 8 y in girls or 9 y in boys. Since the initial discovery of mutations in the maternally imprinted MKRN3 gene in 2013, several case reports have described mutations in this gene in ICPP patients from different populations, highlighting the importance of MKRN3 as a regulator of pubertal onset.


METHODS
We screened 29 Danish girls with ICPP for mutations in MKRN3. Expression of MKRN3 in human hypothalamic complementary DNA (cDNA) was investigated by PCR.


RESULTS
One paternally inherited rare variant, c.1034G>A (p.Arg345His), was identified in one girl with ICPP and in her brother with early puberty. The variant is predicted to be deleterious by three different in silico prediction programs. Expression of MKRN3 was confirmed in adult human hypothalamus.


CONCLUSIONS
Our results are in line with previous studies in which paternally inherited MKRN3 mutations have been found both in males and in females with ICPP or early puberty. Our report further expands the set of MKRN3 mutations identified in ICPP patients across diverse populations, thus supporting the major regulatory function of MKRN3 in pubertal onset.
Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.|Children's Hospital, Helsinki University Hospital, Helsinki, Finland.
Johanna
J
Känsäkoski
Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.|Children's Hospital, Helsinki University Hospital, Helsinki, Finland.
Taneli
T
Raivio
Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
Anders
A
Juul
Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.|Children's Hospital, Helsinki University Hospital, Helsinki, Finland.
Johanna
http://orcid.org/0000-0001-7958-8262
J
Tommiska
D000367:Age Factors; D002648:Child; D003198:Computer Simulation; D004252:DNA Mutational Analysis; D003718:Denmark; D005220:Fathers; D005260:Female; D020022:Genetic Predisposition to Disease; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000627:therapeutic use; D040941:Heredity; D006801:Humans; D008297:Male; D008957:Models, Genetic; D020125:Mutation, Missense; D010375:Pedigree; D010641:Phenotype; D011627:Puberty / Q000187:drug effects / Q000235:genetics*; D011629:Puberty, Precocious / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics* / Q000503:physiopathology; D012261:Ribonucleoproteins / Q000235:genetics*; D012307:Risk Factors; D035781:Siblings; D016896:Treatment Outcome; D044767:Ubiquitin-Protein Ligases
D012261:Ribonucleoproteins; D007987:Gonadotropin-Releasing Hormone; C119425:MKRN3 protein, human; D044767:Ubiquitin-Protein Ligases