Introduction to the special issue: human linkage studies for behavioral traits

Area of Science:

• Behavioral Genetics
• Human Genomics
• Psychiatric Genetics

Background:

• The field of behavior genetics has evolved from estimating gene-environment contributions to identifying specific genes and functional variants for complex human traits.
• This transition is marked by a shift towards genome-wide association studies (GWAS) and linkage analysis for complex behavioral phenotypes.
• The post-Genome era necessitates advanced methods for gene localization and functional variant identification.

Purpose of the Study:

• To present findings from large-scale genome-wide linkage scans for various human complex traits.
• To showcase methodological innovations in the field of behavioral genetics.
• To summarize the initial large-scale efforts in linking genetic regions to behavioral traits.

Main Methods:

• Genome-wide linkage scans were employed to identify chromosomal regions associated with complex traits.
• Statistical methods, including LOD score calculations, were used to assess the significance of linkage.
• Methodological tools and innovations relevant to genetic analysis of behavior were also presented.

Main Results:

• Six papers focused on cognition, reporting overlapping linkage peaks on chromosomes 6p and 14p.
• Studies on addictive behaviors (smoking, alcohol dependence) identified linkage regions on chromosomes 6p, 5q, 4p, and 7q.
• Research on emotionality, depression, and loneliness implicated chromosomes 2q and 12q.

Conclusions:

• This special issue highlights the progress in localizing genes associated with complex human behaviors through genome-wide linkage analysis.
• The findings represent a significant step in understanding the genetic architecture of cognition, addiction, and emotionality.
• The presented studies underscore the utility of large-scale genetic enterprises in advancing behavioral genetics research.