These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Circulating MKRN3 levels decline prior to pubertal onset and through puberty: a longitudinal study of healthy girls. Author: Hagen CP, Sørensen K, Mieritz MG, Johannsen TH, Almstrup K, Juul A. Journal: J Clin Endocrinol Metab; 2015 May; 100(5):1920-6. PubMed ID: 25695892. Abstract: CONTEXT: Puberty is initiated by a complex interaction of suppressing and stimulating factors. Genetic studies of familial central precocious puberty have suggested makorin ring finger protein 3 (MKRN3) as a major inhibitor of GnRH secretion during childhood. Furthermore, genetic variation near MKRN3 (rs12148769) affects age at menarche in healthy girls. OBJECTIVE: The purpose of this study was to evaluate whether serum levels of MKRN3 declined before pubertal onset in healthy girls. DESIGN: This was a population-based longitudinal study of healthy Danish girls and a cohort study of early maturing girls. SETTING: The study was performed in the general community and in a tertiary referral center for pediatric endocrinology. PATIENTS OR OTHER PARTICIPANTS: Healthy girls (n = 38) aged 9.3 years (range, 5.9-11.3 years) at baseline and followed for 6.0 years (2.7-7.6 years) (2006-2014) with blood sampling every 6 months and early maturing girls (n = 13) with breast development ay <8.3 years of age were included. MAIN OUTCOME MEASURES: Serum levels of MKRN3 were measured in 354 samples (median, 9 per girl; range, 2-14 per girl), and genotyping of variants near MKRN3 (rs12148769 and rs12439354) was performed. RESULTS: MKRN3 concentrations declined preceding pubertal onset; the geometric mean (95% confidence interval) 3 years before pubertal onset vs the last visit before pubertal onset was 304 pg/mL (264-350 pg/mL) vs 257 pg/mL (243-273 pg/mL), corresponding to a reduction of 15% (1-27%) (P = .033). In prepubertal girls, circulating MKRN3 correlated negatively with gonadotropin levels: for FSH, r = -0.262 (P = .015) and for LH, r = -0.226 (P = .037). After adjustment, MKRN3 levels were lower in early maturing girls than in age-matched prepubertal girls: 171 pg/mL (<25-333 pg/mL) vs 262 pg/mL (94-624 pg/mL) (P = .051). Genetic variants near MKRN3 did not correlate with serum levels of MKRN3. CONCLUSIONS: Declining levels of circulating MKRN3 preceded pubertal onset. The negative correlation between MKRN3 and gonadotropins further supports MKRN3 as a major regulator of hypothalamic GnRH secretion during childhood. Undetectable or low MKRN3 levels were observed in a subgroup of patients with early onset of puberty.[Abstract] [Full Text] [Related] [New Search]