Level of functioning of siblings and parents of probands of varying degrees of retardation

Carol A. Johnson, Frank Martin Ahern, Ronald C. Johnson

Research output: Contribution to journalArticle

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A further analysis of already published data supports the position that retardates of low ability level less frequently have retarded siblings, retarded parents, and parents low in occupational level than do retardates higher in ability level. The analysis supports the position that there are two types of retarded individuals, persons retarded as a result of gene or chromosomal anomalies, brain injury, etc., who more frequently occur in the lower-level retardate group, and persons whose retardation represents polygenic segregation, who more frequently occur in the higher-level group.

Original languageEnglish (US)
Pages (from-to)473-477
Number of pages5
JournalBehavior Genetics
Issue number4
StatePublished - Oct 1 1976


All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Genetics
  • Genetics(clinical)

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