title: Association Between Hand Digit Ratio (2D:4D) and Nonsyndromic Orofacial Clefts.
abstract: Digit ratio (2D:4D) has been considered to be a marker in studies evaluating an individual's susceptibility to diseases, especially those diseases that show sex differences in their occurrence. We aimed to assess whether 2D:4D ratios are associated with nonsyndromic cleft lip and/or palate (NSCL/P) and verify the existence of a specific pattern of 2D:4D ratio in individuals affected by orofacial clefts.
  
  
  
  This was a case-control study.
  
  
  
  Digital measurements of index and ring finger lengths of both hands of patients with NSCL/P (n = 54) and age- and gender-matched controls (n = 54) were obtained using a digital vernier caliper. Mean ratios between the second and fourth digits were compared. Data were analyzed by Student's t test and Mann-Whitney test with a significance level of 5%.
  
  
  
  No significant difference was found between the mean digit ratios of the right and left hands between the groups for any analysis (P > .05), neither for the whole sample nor for the distributions by type of cleft and by gender.
  
  
  
  Although the development of the fingers and the occurrence of NSCL/P can be regulated by the actions of similar genes, our results are not consistent with an association between 2D:4D ratio and this craniofacial deformity. This suggests that intrauterine exposure to fetal androgens, assessed using this marker, is similar between patients with NSCL/P and healthy individuals. We highlight the need for further studies in populations with different ancestries.
authors.forename: Patrícia Helena Costa
authors.initials: PHC
authors.lastname: Mendes
authors.forename: Camila Reis
authors.initials: CR
authors.lastname: Barbosa
authors.forename: Myriam Thatyana Miranda Esteves
authors.initials: MTME
authors.lastname: da Silva
authors.forename: Lívia Máris Ribeiro
authors.initials: LMR
authors.lastname: Paranaíba
authors.forename: Daniela Reis Barbosa
authors.initials: DRB
authors.lastname: Martelli
authors.forename: Letízia Monteiro
authors.initials: LM
authors.lastname: de Barros
authors.forename: Mário Sérgio Oliveira
authors.initials: MSO
authors.lastname: Swerts
authors.forename: Marise Fagundes
authors.initials: MF
authors.lastname: Silveira
authors.forename: Hercílio Martelli
authors.initials: HM
authors.lastname: Júnior
mesh_terms: D000328:Adult; D000886:Anthropometry; D015415:Biomarkers; D016022:Case-Control Studies; D002971:Cleft Lip; D002972:Cleft Palate; D005260:Female; D005385:Fingers / Q000033:anatomy & histology*; D006225:Hand / Q000033:anatomy & histology*; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers
keywords: 2D:4D; cleft lip; cleft palate; digit ratio