High Frequency of MKRN3 Mutations in Male Central Precocious Puberty Previously Classified as Idiopathic
NEUROENDOCRINOLOGY
Authors: Bessa, Danielle S.; Macedo, Delanie B.; Brito, Vinicius N.; Franca, Monica M.; Montenegro, Luciana R.; Cunha-Silva, Marina; Silveira, Leticia G.; Hummel, Tiago; Bergada, Ignacio; Braslavsky, Debora; Abreu, Ana Paula; Dauber, Andrew; Mendonca, Berenice B.; Kaiser, Ursula B.; Latronico, Ana Claudia
Abstract
Background/Aims: Recently, loss-of-function mutations in the MKRN3 gene have been implicated in the etiology of familial central precocious puberty (CPP) in both sexes. We aimed to analyze the frequency of MKRN3 mutations in boys with CPP and to compare the clinical and hormonal features of boys with and without MKRN3 mutations. Methods: This was a retrospective review of clinical, hormonal and genetic features of 20 male patients with idiopathic CPP evaluated at an academic medical center. The entire coding regions of MKRN3, KISS1 and KISS1R genes were sequenced. Results: We studied 20 boys from 17 families with CPP. All of them had normal brain magnetic resonance imaging. Eight boys from 5 families harbored four distinct heterozygous MKRN3 mutations predicted to be deleterious for protein function, p.Ala162Glyfs*14, p.Arg213Glyfs*73, p.Arg328Cys and p. Arg365Ser. One boy carried a previously described KISS1-activating mutation (p.Pro74Ser). The frequency of MKRN3 mutations among these boys with idiopathic CPP was significantly higher than previously reported female data (40 vs. 6.4%, respectively, p < 0.001). Boys with MKRN3 mutations had typical clinical and hormonal features of CPP. Notably, they had later pubertal onset than boys without MKRN3 abnormalities (median age 8.2 vs. 7.0 years, respectively, p = 0.033). Conclusion: We demonstrated a high frequency of MKRN3 mutations in boys with CPP, previously classified as idiopathic, suggesting the importance of genetic analysis in this group. The boys with CPP due to MKRN3 mutations had classical features of CPP, but with puberty initiation at a borderline age. (C) 2016 S. Karger AG, Basel
Kisspeptin Protein in Seminal Plasma Is Positively Associated with Semen Quality: Results from the MARHCS Study in Chongqing, China
BIOMED RESEARCH INTERNATIONAL
Authors: Zou, Peng; Wang, Xiaogang; Chen, Qing; Yang, Huan; Zhou, Niya; Sun, Lei; Chen, Hongqiang; Liu, Jinyi; Ao, Lin; Cui, Zhihong; Cao, Jia
Abstract
Objectives. To study the associations between kisspeptin levels in seminal plasma and blood plasma and semen quality. Materials and Methods. We conducted a male reproductive health survey in June 2014. A total of 666 volunteers were recruited from colleges in Chongqing, China. All volunteers completed a questionnaire including information on domestic characteristics and some potential confounders. We tested the kisspeptin levels in both blood and seminal plasma. Total seminal kisspeptin was calculated as the concentration of kisspeptin in seminal plasma multiplied by semen volume. Semen samples were tested according to the 2010 World Health Organization's (WHO) guidelines. Spearman correlation and multivariate linear regression were used to explore the association between kisspeptin concentrations in seminal plasma and blood plasma and semen quality. Potential confounders that were adjusted for included age, abstinence time, body mass index (BMI), grade, and smoking. Results. The median of kisspeptin levels in seminal plasma was 60,000 times higher than kisspeptin in blood plasma (28.0 x 10(6)pg/ml versus 448.9pg/ml). Each interquartile range (IQR) of kisspeptin in seminal plasma was associated with a 4.6% (95% confidence interval [CI]: 1.6%-7.6%) increase in sperm concentration. Each IQR of total kisspeptin was associated with a 7.7% (95% CI: 4.4%-11.0%) increase in total sperm number and a 7.8% (95% CI: 4.0%-11.7%) increase in total motile sperm count. Kisspeptin levels were further classified into quartiles and Q1 was set as the reference level. Subjects in the high total kisspeptin group had 57.5% (95% CI: 33.2%-86.2%) higher total sperm number than the reference group. Conclusion. The positive association between kisspeptin levels in seminal plasma and semen quality supported an important role for the KISS1/GPR54 system in male reproductive health. Kisspeptin may be a potential marker of male reproductive health and an alternative strategy for treating infertility.