Expansion of a novel CAG trinucleotide repeat in the 5′ region of PPP2R2B is associated with SCA12

Evidence of a Common Founder for SCA12 in the Indian Population

“…Repeat sizes for the CAG repeat were estimated at the PPP2R2B locus by PCR with previously published primers (Holmes et al 1999) using GeneScan software on an ABI Prism 377 Automated DNA Sequencer (Perkin Elmer, Foster City, CA, USA).…”

“…This has been attributed to the ethnicity, diversity and inherent genetic differences between sub-populations. SCA12, first reported in a large American pedigree of German descent (Holmes et al 1999;O'Hearn et al 2001) has been subsequently reported only in Indian families (Fujigasaki et al 2001;Srivastava et al 2001). In an earlier study, expansion in the PPP2R2B gene was reported in 6 patient, and 3 asymptomatic at-risk individual, in 5 Indian families (Srivastava et al 2001), which suggested that SCA12 is not rare in India.…”

“…In normal individuals, the CAG repeat length is highly polymorphic and ranges from 7-32 triplets. The length of previously reported expanded alleles is 55-78 triplets (Holmes et al 1999;Fujigasaki et al 2001). The hallmark of SCA12 is an action tremor of the upper extremities followed by a wide range of signs and symptoms, including mild cerebellar dysfunction, hyperreflexia, parkinsonian features or cognitive dysfunction.…”

Spectrum and prevalence of autosomal dominant spinocerebellar ataxia in Hokkaido, the northern island of Japan: a study of 113 Japanese families

“…To date, 29 different genetic loci have been reported to be responsible for ADCA (http://www.gene.ucl.ac.uk/cgi-bin/nomenclature): spinocerebellar ataxia type 1 (SCA1) on chromosome 6p22-p23 (Orr et al 1993); SCA2 on 12q23-q24.1 (Imbert et al 1996;Sanpei et al 1996); Machado-Joseph disease (MJD)/ SCA3 on 14q24.3-q32.1 (Kawaguchi et al 1994); SCA4 on 16q22.1 (Flanigan et al 1996); SCA5 on 11q13.2 (Ranum et al 1994); SCA6 on 19p13.1 (Zhuchenko et al 1997); SCA7 on 3p12-p13 (David et al 1997); SCA8 on 13p (Koob et al 1999); SCA10 on 22q13-qter. (Matsuura et al 2000); SCA11 on 15q14-q21.3 (Worth et al 1999); SCA12 on 5q31-33 (Holmes et al 1999);SCA13 on 19q13.3-q13.4 (Waters et al 2006); SCA14 on 19q13.42 Chen et al 2003;Yabe et al 2003); SCA15 on 3p24.2 (Gardner et al 2005); SCA16 on 8q23-q24.1 (Miyoshi et al 2001); SCA17 on 6q27 (Nakamura et al 2001); SCA18 on 7q22 (Brkanac et al 2002); SCA19 on 1p21-q21 (Verbeek et al 2002); SCA20 on 11p11.2-q13.3 (Knight et al 2004); SCA21 on 7p21.3-p15.1 (Vuillaume et al 2002); SCA22 on 1p21-q23 (Chung et al 2003); SCA23 on 20p13-p12 (Verbeek et al 2004); SCA24 on 1p26 (Swartz et al 2002); SCA25 on 2p21-p15 (Stevanin et al 2004); SCA26 on 19p13.3 (Yu et al 2005); SCA27 on 13q33.1 (Van Swieten et al 2003); SCA28 on 18p11.22-q11.2 (Cagnoli et al 2006); SCA 29 on 3p26 (Dudding et al 2004) and dentatorubral pallidoluysian atrophy (DRPLA) on 12p13.31 (Koide et al 1994;Nagafuchi et al 1994). Among these loci, causative genes have been further identified containing trinucleotide repeats (CAG) in S...…”

“…(Matsuura et al 2000); SCA11 on 15q14-q21.3 (Worth et al 1999); SCA12 on 5q31-33 (Holmes et al 1999);SCA13 on 19q13.3-q13.4 (Waters et al 2006); SCA14 on 19q13.42 Chen et al 2003;Yabe et al 2003); SCA15 on 3p24.2 (Gardner et al 2005); SCA16 on 8q23-q24.1 (Miyoshi et al 2001); SCA17 on 6q27 (Nakamura et al 2001); SCA18 on 7q22 (Brkanac et al 2002); SCA19 on 1p21-q21 (Verbeek et al 2002); SCA20 on 11p11.2-q13.3 (Knight et al 2004); SCA21 on 7p21.3-p15.1 (Vuillaume et al 2002); SCA22 on 1p21-q23 (Chung et al 2003); SCA23 on 20p13-p12 (Verbeek et al 2004); SCA24 on 1p26 (Swartz et al 2002); SCA25 on 2p21-p15 (Stevanin et al 2004); SCA26 on 19p13.3 (Yu et al 2005); SCA27 on 13q33.1 (Van Swieten et al 2003); SCA28 on 18p11.22-q11.2 (Cagnoli et al 2006); SCA 29 on 3p26 (Dudding et al 2004) and dentatorubral pallidoluysian atrophy (DRPLA) on 12p13.31 (Koide et al 1994;Nagafuchi et al 1994). Among these loci, causative genes have been further identified containing trinucleotide repeats (CAG) in SCA1, SCA2, SCA3, SCA6, SCA7, SCA17, DRPLA (Orr et al 1993;Sanpei et al 1996;Kawaguchi Y et al 1994;Zhuchenko et al 1997;David et al 1997;Nakamura et al 2001;Koide et al 1994), and in the promoter region of PPP2R2B related to SCA12 (Holmes et al 1999); trinucleotide repeats (CTG) within an untranslated region of the SCA8 gene (Koob et al 1999); and a pentanucleotide (ATTCT) repeat expansion within intron 9 of the SCA10 gene (Matsuura et al 2000). Whi...…”