Loci on chromosomes 14 and 2, distinct from ABCG5/ABCG8, regulate plasma plant sterol levels in a C57BL/6J x CASA/Rk intercross.
Plasma plant sterol levels differ among humans due to genetic and dietary factors. A disease characterized by high plasma plant sterol levels, beta-sitosterolemia, was recently found to be due to mutations at the ABCG5ABCG8 locus. To detect variants at this and other loci, a genetic cross was carried out between two laboratory mouse strains. Parental C57BL6J had almost twice the campesterol and sitosterol levels compared with parental CASARk mice, and F(1) mice had levels halfway between the parentals. An intercross between F(1)s was performed and plasma plant sterol levels measured in 102 male and 99 female F(2) mice. Plasma plant sterols in F(2)s displayed a unimodal distribution, suggesting the effects of several rather a single major gene. In the F(2) mice, a full genome scan revealed significant linkages on chromosomes 14 and 2. With regard to chromosome 14, analysis showed a single peak for linkage at 17 cM with a logarithm of odds (LOD) score of 9.9, designated plasma plant sterol 14 (Plast14). With regard to chromosome 2, analysis showed two significant peaks for linkage at 18 and 65 cMs with LOD scores of 4.1 and 3.65, respectively, designated Plast2a and Plast2b, respectively. Four interactions between loci, predominantly of an additive nature, were also demonstrated, the most significant between Plast14 and Plast2b (LOD 16.44). No significant linkage or gene interaction was detected for the ABCG5ABCG8 locus on chromosome 17. Therefore, other genes besides ABCG5ABCG8 influence plasma plant sterol levels and now become candidates to explain differences in plasma plant sterol levels between humans.
Sehayek
Ephraim
E
Laboratory of Biochemical Genetics and Metabolism, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. sehayek@rockefeller.edu
Duncan
Elizabeth M
EM
Lutjohann
Dieter
D
Von Bergmann
Klaus
K
Ono
Jennie G
JG
Batta
Ashok K
AK
Salen
Gerald
G
Breslow
Jan L
JL
D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D000071019:ATP Binding Cassette Transporter, Subfamily G, Member 8; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000818:Animals; D015415:Biomarkers; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000097:blood* / Q000493:pharmacokinetics; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D004041:Dietary Fats / Q000493:pharmacokinetics; D004843:Epistasis, Genetic; D005260:Female; D005838:Genotype; D008074:Lipoproteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D010840:Phytosterols; D012855:Sitosterols / Q000097:blood* / Q000493:pharmacokinetics; D013045:Species Specificity
C462600:ABCG5 protein, mouse; C462601:ABCG8 protein, mouse; D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D000071019:ATP Binding Cassette Transporter, Subfamily G, Member 8; D018528:ATP-Binding Cassette Transporters; D015415:Biomarkers; D004041:Dietary Fats; D008074:Lipoproteins; D010840:Phytosterols; D012855:Sitosterols; C021273:campesterol; C025473:gamma-sitosterol; D002784:Cholesterol