title: Consanguinity and eye diseases with a potential genetic etiology. Data from a prevalence study in Andhra Pradesh, India.
abstract: OBJECTIVE
  To determine the prevalence of consanguinity and its potential associations with eye diseases in Andhra Pradesh state of south India.
  
  
  METHODS
  As part of a demographic interview schedule, prior to clinical examinations, trained investigators collected information regarding consanguinity of the parents from subjects randomly chosen for a population-based cross-sectional epidemiological study. Each subject underwent a detailed ocular examination including visual acuity measurements, anterior segment examinations with slit-lamp biomicroscopy, and posterior segment examinations. Adjusted odds ratios (OR), attributable risks (AR) and population attributable risks (PAR) were estimated.
  
  
  RESULTS
  We obtained details regarding consanguinity of the parents from 10,290 of the 10,293 subjects who were enumerated and examined in the study. Parental consanguinity was reported by 1822 (24.7%) rural subjects and 782 (32.9%) urban subjects. Eighty (0.008%, 95% CI: 0.006, 0.010) of the 9757 subjects had an ocular disease with a potential genetic basis. We found microcornea to be significantly associated with both an uncle-niece relationship (adjusted OR: 7.32, 95% CI: 1.73, 30.97, AR = 86.34%, PAR = 42.11%) and a first-cousin relationship between the parents (adjusted OR 4.51, 95% CI: 1.05, 19.40, AR = 77.83%, PAR = 29.02%). Retinitis pigmentosa was significantly associated with a first-cousin relationship between the parents (adjusted OR: 5.31, 95% CI: 1.00, 28.25, AR = 81.17%, PAR = 33.43%).
  
  
  CONCLUSIONS
  The high prevalence of consanguinity in this population does not appear to translate into a high prevalence of ocular malformations; however, studies with larger sample sizes are required to further explore the strength of these associations.
authors.affiliation: International Centre for Advancement of Rural Eye Care, L.V. Prasad Eye Institute, Hyderabad, Andhra Pradesh, India. praveen@icare.stph.net
authors.forename: Praveen K
authors.initials: PK
authors.lastname: Nirmalan
authors.forename: Sannapaneni
authors.initials: S
authors.lastname: Krishnaiah
authors.forename: Rishita
authors.initials: R
authors.lastname: Nutheti
authors.forename: Bindiganavale R
authors.initials: BR
authors.lastname: Shamanna
authors.forename: Gullapalli N
authors.initials: GN
authors.lastname: Rao
authors.forename: Ravi
authors.initials: R
authors.lastname: Thomas
mesh_terms: D000293:Adolescent; D000328:Adult; D003241:Consanguinity; D005128:Eye Diseases / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012424:Rural Population; D014505:Urban Population