title: Genetic variants of estrogen beta and leptin receptors may cause gynecomastia in adolescent.
abstract: OBJECTIVE
  Gynecomastia is a benign breast enlargement in males that affects approximately one-third of adolescents. The exact mechanism is not fully understood; however, it has been proposed that estrogen receptors and aromatase enzyme activity may play important roles in the pathogenesis of gynecomastia. While many studies have reported that aromatase enzyme (CYP19) gene polymorphism is associated with gynecomastia, only one study has shown a relationship between estrogen receptor (ER) alpha and beta gene polymorphism and gynecomastia. Thus, the aim of this study was to evaluate the relationships between CYP19 (rs2414096), ER alpha (rs2234693), ER beta (rs4986938), leptin (rs7799039), and leptin receptor (rs1137101) gene polymorphisms and gynecomastia.
  
  
  METHODS
  This study included 107 male adolescents with gynecomastia and 97 controls. Total serum testosterone (T) and estradiol (E2) levels were measured, and DNA was extracted from whole blood using the PCR-RFLP technique. The polymorphic distributions of CYP19, ER alpha, ER beta, leptin and leptin receptor genes were compared.
  
  
  RESULTS
  The median E2 level was 12.41 (5.00-65.40) pg/ml in the control group and 16.86 (2.58-78.47) pg/ml in the study group (p<0.001). The median T level was 2.19 (0.04-7.04) ng/ml in the control group and 1.46 (0.13-12.02) ng/ml in the study group (p=0.714). There was a significant relationship between gynecomastia and leptin receptor rs1137101 (p=0.002) and ER beta receptor rs4986938 gene polymorphisms (p=0.002).
  
  
  CONCLUSIONS
  According to our results, increased E2 level and ER beta gene rs4986938 polymorphism might explain why some adolescents have gynecomastia. Leptin receptor gene rs1137101 polymorphism might affect susceptibility to gynecomastia.
authors.affiliation: Harran University, School of Medicine, Department of Pediatric Endocrinology, Sanliurfa, Turkey. Electronic address: dreeren@gmail.com.
authors.forename: Erdal
authors.initials: E
authors.lastname: Eren
authors.affiliation: School of Health Sciences, Mugla Sitki Kocman University, Mugla, Turkey.
authors.forename: Tuba
authors.initials: T
authors.lastname: Edgunlu
authors.affiliation: Pediatric Endocrinology Clinic, Dr. Behçet Uz Children's Research and Training Hospital, Izmir, Turkey.
authors.forename: Huseyin Anil
authors.initials: HA
authors.lastname: Korkmaz
authors.affiliation: Pediatric Endocrinology Clinic, Mersin Hospital of Women and Children's Health and Diseases, Mersin, Turkey.
authors.forename: Esra Deniz Papatya
authors.initials: ED
authors.lastname: Cakir
authors.affiliation: Pediatric Endocrinology Clinic, Gaziantep Children Hospital, Gaziantep, Turkey.
authors.forename: Korcan
authors.initials: K
authors.lastname: Demir
authors.affiliation: Department of Medical Biology, School of Medicine, Mugla Sitki Kocman University, Mugla, Turkey.
authors.forename: Esin Sakalli
authors.initials: ES
authors.lastname: Cetin
authors.affiliation: Department of Medical Genetics, School of Medicine, Bulent Ecevit University, Zonguldak, Turkey.
authors.forename: Sevim Karakas
authors.initials: SK
authors.lastname: Celik
mesh_terms: D000293:Adolescent; D001141:Aromatase / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D004958:Estradiol / Q000097:blood; D047628:Estrogen Receptor alpha / Q000235:genetics*; D047629:Estrogen Receptor beta / Q000235:genetics*; D004967:Estrogens / Q000097:blood; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006177:Gynecomastia / Q000235:genetics* / Q000473:pathology; D006239:Haplotypes; D006801:Humans; D020738:Leptin / Q000097:blood / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D011627:Puberty; D054411:Receptors, Leptin / Q000235:genetics*; D013739:Testosterone / Q000097:blood; D014421:Turkey
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004967:Estrogens; C515448:LEPR protein, human; D020738:Leptin; D054411:Receptors, Leptin; D013739:Testosterone; D004958:Estradiol; D001141:Aromatase
keywords: Estrogen; Gynecomastia; Leptin; Polymorphism; Puberty