Human muscle acetylcholine receptor alpha-subunit gene (CHRNA1) association with autoimmune myasthenia gravis in black, mixed-ancestry and Caucasian subjects.
We have sought associations with the muscle acetylcholine receptor alpha-subunit gene (CHRNA1) in autoimmune myasthenia gravis (MG) patients from three ethnic groups; Caucasians and South Africans of Black and Mixed-Ancestry. We found a significant association with the HB*15 CA repeat allele in unrelated Black myasthenics (n = 18; RR = 2.85; pX2 = 0.04) compared with 52 ethnically matched controls. A family-based association study and linkage analysis in Caucasian simplex and multiplex families supported a positive association at this locus with the longer alleles, including HB*14 to *18. However, no significant cosegregation of the disease with the HB alleles could be demonstrated in affected sib pairs. Our results suggest that the CHRNA1 locus harbours a minor susceptibility gene for developing MG, though we cannot rule out linkage disequilibrium with another major gene locus on chromosome 2.
Heckmann
J M
JM
Neurosciences Group, Institute of Molecular Medicine, Oxford, UK.
Morrison
K E
KE
Emeryk-Szajewska
B
B
Strugalska
H
H
Bergoffen
J
J
Willcox
N
N
Newsom-Davis
J
J
D015415:Biomarkers; D044383:Black People / Q000235:genetics*; D016022:Case-Control Studies; D006801:Humans; D009132:Muscles / Q000378:metabolism*; D009157:Myasthenia Gravis / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D011950:Receptors, Cholinergic / Q000235:genetics*; D044465:White People / Q000235:genetics*
D015415:Biomarkers; D011950:Receptors, Cholinergic