The contactin 4 gene locus at 3p26 is a candidate gene of SCA16.
OBJECTIVE
To identify of the gene responsible for the onset of spinocerebellar ataxia type 16 (SCA16).


METHODS
We reanalyzed the linkage of the original Japanese pedigree using updated information, including three additional subjects. We then screened all exons located in the critical region.


RESULTS
We reassigned the locus of SCA16 to 3p26.2-pter (maximum logarithm-of-odds score = 5.177) and identified only one point mutation (4,256C-->T) in the 3' untranslated region of the contactin 4 gene (CNTN4) on chromosome 3p26.2-26.3, which cosegregated with the disease. This mutation was not detected in 520 control subjects; moreover, we revised the phenotype of SCA16 from pure to complicated SCA.


CONCLUSIONS
The contactin 4 gene (CNTN4) is associated with cerebellar degeneration in spinocerebellar ataxia type 16. Additional studies are necessary to prove 4,256C-->T to be a causative mutation.
Miura
S
S
Division of Respirology and Neurology, Department of Medicine, Kurume University School of Medicine, Kurume City, Fukuoka, Japan. shiroh46@med.kurume-u.ac.jp
Shibata
H
H
Furuya
H
H
Ohyagi
Y
Y
Osoegawa
M
M
Miyoshi
Y
Y
Matsunaga
H
H
Shibata
A
A
Matsumoto
N
N
Iwaki
A
A
Taniwaki
T
T
Kikuchi
H
H
Kira
J
J
Fukumaki
Y
Y
D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics*; D002874:Chromosome Mapping; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics*; D058966:Contactins; D004252:DNA Mutational Analysis; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing / Q000379:methods*; D006579:Heterozygote; D006801:Humans; D007564:Japan; D015810:Linkage Disequilibrium / Q000235:genetics*; D008297:Male; D010375:Pedigree; D020754:Spinocerebellar Ataxias / Q000235:genetics*
C098304:CNTN4 protein, human; D015816:Cell Adhesion Molecules, Neuronal; D058966:Contactins