Unique origin and specific ethnic distribution of the Friedreich ataxia GAA expansion.
The GAA triplet repeat expansion that causes Friedreich ataxia is found only in individuals of European, North African, Middle Eastern, or Indian origin (Indo-European and Afro-Asiatic speakers). Analysis of normal alleles of the GAA repeat and of closely linked markers suggests that expansions arose through a unique two-step process. A major implication of these findings is that Friedreich ataxia may not exist among sub-Saharan Africans, Amerindians, and people from China, Japan, and Southeast Asia.
Labuda
M
M
Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec, Canada. massimo.pandolfo@umontreal.ca
Labuda
D
D
Miranda
C
C
Poirier
J
J
Soong
B W
BW
Barucha
N E
NE
Pandolfo
M
M
D000352:Africa, Northern; D000483:Alleles; D001208:Asia; D044466:Asian People / Q000235:genetics; D044383:Black People / Q000235:genetics; D005060:Europe; D018703:Founder Effect; D005621:Friedreich Ataxia / Q000208:ethnology* / Q000235:genetics*; D008040:Genetic Linkage; D005819:Genetic Markers; D006239:Haplotypes; D006801:Humans; D033862:Iron-Binding Proteins; D008877:Middle East; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*; D044465:White People / Q000235:genetics; D000096923:Frataxin
D005819:Genetic Markers; D033862:Iron-Binding Proteins; D017853:Phosphotransferases (Alcohol Group Acceptor); D000096923:Frataxin