Complex Multifactorial Genetic Diseases


Variation in traits can be due to genetic factors or the environment – nature versus nurture – or, more likely, to a combination of both. It can be of interest, especially when a trait is detrimental, to localize the regions of the genome that contain the genes involved and, beyond that, to map them and specific risk variants. Understanding the possible roles that genes may play in trait variation and, furthermore, estimating or modelling the genetic component are important first steps to inform subsequent genetic studies. There are many different study designs and genetic analysis techniques, each with their respective strengths and weaknesses for the identification of risk variants. Knowledge of disease susceptibility genes may help in the quest for new treatments and cures.

Key Concepts:

  • Types of trait variation

  • The possible roles of genes in trait variation

  • The components of phenotypic variation

  • Study designs for the estimation of genetic effects and heritability

  • The concept of genetic heterogeneity

  • Types of genetic study designs

  • Various analysis techniques used in genetic studies

Keywords: genetic disease; phenotype; heterogeneity; linkage; association


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How to Cite close
Camp, Nicola J, and Bansal, Aruna(Sep 2009) Complex Multifactorial Genetic Diseases. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0001881.pub2]