Behavior Genetics

, Volume 18, Issue 5, pp 583–594 | Cite as

Consequences of consanguinity on cognitive behavior

  • Mohammad Afzal


In order to study the effects of consanguinity on IQ, a survey was conducted among the Ansari Muslims of Bhagalpur residing in suburban and rural areas. Both outbred (N=390 from suburban areas andN=358 from rural areas) and inbred (N's=300 and 266, respectively) children aged 9 to 12 years from socioeconomically middle-class families were administered the Weschler Intelligence Scale for Children—Revised [WISC(R)-74]. The coefficient of inbreeding, F, was .0625. The inbred children showed lower verbal (20 and 22%) and performance (30 and 20%) subtest scores and lower verbal (11 and 11%), performance (17 and 12%), and full-scale (15 and 12%) IQs. A three-factor analysis of variance performed on the full-scale IQ scores indicated that both consanguinity and locality affect IQ. The interaction between these two facors was also significant. Neither age nor sex affected these scores. Overall, subjects' performance scores were lower than verbal scores.

Key Words

consanguinity inbreeding IQ Weschler Intelligence Scale for Children—Revised [WISC)R)-74] rural-suburban Ansari Muslims 


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Copyright information

© Plenum Publishing Corporation 1988

Authors and Affiliations

  • Mohammad Afzal
    • 1
  1. 1.Genetics Laboratory, Post-Graduate Department of ZoologyBhagulpur UniversityBhagalpurIndia

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