title: Association study of common mitochondrial variants and cognitive ability.
abstract: Mitochondria are central to optimal functioning of the nervous system and disruption of mitochondrial function is known to lead to cognitive impairment. However, there has been little focus on whether common mitochondrial DNA polymorphisms contribute to normal variation in cognitive phenotypes. In this study, we use methodology for carrying out whole mitochondrial association studies in family cohorts to test whether 69 common mitochondrial variants and 10 common European haplogroups are associated with a number of measures of cognition, including information processing, word recognition and general cognitive ability, in a sample of Australian adolescent twins and their singleton/non-twin siblings. With data from 1,385 individuals from 665 families, this is by far the largest mitochondrial association study of cognition undertaken to date. We find that there is no significant evidence that either common European mitochondrial SNPs or haplogroups are associated with variation in cognitive performance. In spite of the associations not reaching significance, several of the most highly associated SNPs are in mitochondrial genes that have previously been identified as potentially playing a role in cognitive performance in mice. These genes warrant further investigation in both functional and association studies with larger cohorts.
authors.affiliation: Queensland Statistical Genetics, Queensland Institute of Medical Research, 300 Herston Road, Brisbane, QLD, 4029, Australia. enda.byrne@qimr.edu.au
authors.forename: Enda M
authors.initials: EM
authors.lastname: Byrne
authors.forename: Allan F
authors.initials: AF
authors.lastname: McRae
authors.forename: David L
authors.initials: DL
authors.lastname: Duffy
authors.forename: Zhen Zhen
authors.initials: ZZ
authors.lastname: Zhao
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Martin
authors.forename: Margaret J
authors.initials: MJ
authors.lastname: Wright
authors.forename: Grant W
authors.initials: GW
authors.lastname: Montgomery
authors.forename: Peter M
authors.initials: PM
authors.lastname: Visscher
mesh_terms: D000293:Adolescent; D000328:Adult; D001315:Australia; D003072:Cognition Disorders / Q000235:genetics*; D015331:Cohort Studies; D004272:DNA, Mitochondrial / Q000235:genetics*; D005060:Europe; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D008928:Mitochondria / Q000378:metabolism*; D020641:Polymorphism, Single Nucleotide; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic
chemical_list: D004272:DNA, Mitochondrial