The genetic and environmental etiology of novel frequency-driven regional parcellations of abnormal white matter

Shu-Ju Lin1,2, Nathan A Gillespie3,4, Randy Notestine5

  • 1Department of Psychiatry, University of California, San Diego, La Jolla, California, USA.

Insights

Genetic factors significantly influence white matter disease patterns in aging brains. This study identified substantial heritability for abnormal white matter signals across distinct brain regions.

Area of Science:

  • Neuroimaging
  • Genetics
  • Aging Research

Background:

  • White matter disease prevalence rises with age, linked to cognitive decline and dementia risk.
  • Magnetic Resonance Imaging (MRI) quantifies white matter damage, but regional patterns may have distinct genetic or environmental origins.

Purpose of the Study:

  • To develop and apply a novel data-driven parcellation approach for analyzing regional white matter abnormalities.
  • To investigate the genetic and environmental influences on distinct white matter regions using biometrical twin modeling.

Main Methods:

  • Utilized Vietnam Era Twin Study of Aging (VETSA) data (n=475, mean age 67.6 years).
  • Created a probability distribution atlas and applied a watershed algorithm for regional parcellation.
  • Performed multivariate biometrical twin modeling on five defined anatomical regions.

Main Results:

  • Additive genetic influences fully explained family aggregation of white matter abnormalities.
  • Heritability estimates for abnormal white matter (AWM) ranged from 0.69 to 0.79 across regions.
  • Genetic correlations between regions were mostly moderate to high (0.57-0.85), indicating shared genetic influences, with some smaller correlations (0.35-0.39) suggesting unique genetic effects.

Conclusions:

  • The novel data-driven parcellations are valuable for dissecting genetic and environmental contributions to white matter disease.
  • This approach provides a foundation for future research into the etiology of age-related white matter changes and their impact on cognition.