title: Relationship of 2D:4D finger ratio with androgen receptor CAG and GGN repeat polymorphism.
abstract: OBJECTIVE
  The relative length of the second-to-fourth digits (2D:4D) has been linked with prenatal androgen in humans. A recent study shows that the 2D:4D ratio in mice is controlled by the balance of androgen to estrogen signaling during a narrow window of digit development. Androgen receptor (AR) activity is higher in digit 4 than in digit 2, and inactivation of AR decreases growth of digit 4, which causes a higher 2D:4D ratio. At the molecular level, the effect of androgens is mediated through the activation of AR. The CAG/GGN repeat polymorphisms of the AR gene are associated with AR activity. Here, we investigate the effect of CAG/GGN repeat polymorphisms in AR on 2D:4D in Chinese.
  
  
  METHODS
  Digit lengths of the second and fourth fingers were measured from photocopies of the ventral surface of the hand and by actual finger measurements. We genotyped AR polymorphisms by ABI 3730 DNA analyzer.
  
  
  RESULTS
  We found that left hand 2D:4D ratio was longer than that of the right hand both in males and in females. We failed to find any relationship between CAG / GGN alleles and the left hand, right hand, right minus left-hand or mean hand 2D:4D ratios (all, r < 0.20, P > 0.05).
  
  
  CONCLUSIONS
  In this study, we first found that the left hand 2D:4D ratio was longer than that of the right hand in both males and females. However, we found that both CAG and GGN alleles were not associated with the left hand, right hand, right minus left-hand or mean hand 2D:4D ratios.
authors.affiliation: Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Yinchuan, Ningxia 750004, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Dang
authors.forename: Liguo
authors.initials: L
authors.lastname: Pei
authors.forename: Mengjing
authors.initials: M
authors.lastname: Guo
authors.forename: Hao
authors.initials: H
authors.lastname: Zhu
authors.forename: Lei
authors.initials: L
authors.lastname: Qu
authors.forename: Fei
authors.initials: F
authors.lastname: Jia
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
authors.forename: Zhenghao
authors.initials: Z
authors.lastname: Huo
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D000704:Analysis of Variance; D000886:Anthropometry; D005260:Female; D005385:Fingers / Q000033:anatomy & histology*; D005838:Genotype; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic; D011944:Receptors, Androgen / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D055815:Young Adult
chemical_list: D011944:Receptors, Androgen