Spinocerebellar ataxias: genetic subtypes

Last update: November 29, 2018

Spinocerebellar ataxias are a group of clinically and genetically heterogeneous disorders. We list below an update on all genetic subtypes, including the most recently identified ones, based on mode of inheritance (Table 1: autosomal dominant; Table 2: autosomal recessive; Table 3: X-linked). Chromosomal locus, gene, mutational spectrum and testing methods are given. Because of significant clinical overlap, multigene and multi-method panel testing is recommeded. To see all our spinocerebellar ataxia panels available for testing click here.

Table 1 – Autosomal dominant spinocerebellar ataxias

Recommended testing
SubtypeLocusGeneMutational spectrumFLA/RPASeqDel/dup
SCA16p22.3ATXN1REx
SCA212q24.12ATXN2REx
SCA314q24.3-q31ATXN3REx
SCA416q22.1unknownunknown
SCA511q13.2SPTBN2Px
SCA619p13.2CACNA1ARE, Pxx
SCA73p14.1ATXN7REx
SCA813q21ATXN8OSREx
SCA9unknownunknownunknown
SCA1022q13.31ATXN10REx
SCA1115q15.2TTBK2Px
SCA125q32PPP2R2BREx
SCA1319q13.33KCNC3Px
SCA1419q13.42PRKCGPx
SCA153p26.1ITPR1D, Pxx
SCA16see SCA15
SCA176q27TBPREx
SCA187q22-q32unknownunknown
SCA191p1.,2KCND3P
SCA2011q21variDx
SCA211p36.33TMEM240Px
SCA22see SCA19
SCA2320p13PDYNPx
SCA24see SCAR4
SCA252p21-p13unknownunknown
SCA2619p13.3? EEF2Px
SCA2713q33.1FGF14Px
SCA2818p11.21AFG3L2Px
SCA293p26.1ITPR1D, Pxx
SCA304q34.3-q35.1unknownunknown
SCA3116q21BEAN1Ix
SCA327q32-q33unknownunknown
SCA33not class.
SCA346q14.1ELOVL4Px
SCA3520p13TGM6Px
SCA3620p13NOP56REx
SCA371p32unkownunknown
SCA386p12.1ELOVL5Px
SCA39not class.
SCA4014q32.11-q32.12? CCDC88CPx
SCA414q27TRPC3Px
SCA4217q21.33CACNA1GPx
SCA433q25.2? MMEPx
SCA446q24.3GRM1Px
SCA455q33.1FAT2Px
SCA4619q13.2? PLD3Px
SCA471p35.2PUM1Px
SCA4816p13.3? STUB1Px

Legend: RE: repeat expansion; P: punctiform (single nucleotide variations, small indels); D: large deletions or duplications; I: large insertion; FLA/RPA: fragment length analysis/repeat primed assay; Seq: sequencing; Del/dup: large deletions/duplications testing (MLPA/qPCR); the question point (?) indicates that the mutation has been detected in one single family or one single patient, so that the subtype needs to be confirmed.

Tabella 2 – Autosomal recessive spinocerebellar ataxias

Recommended testing
SubtypeLocusGeneMutational spectrumFLA/RPASeqDel/dup
SCAR19q34.13SETXP, Dxx
SCAR29q34.3PMPCAP x
SCAR36p23-p21unknown
SCAR41p36unknown
SCAR515q25.3ZNF592Px
SCAR620q11-q13unkown
SCAR711p15.4TPP1Px
SCAR86q25.1-q25.2SYNE1Px
SCAR91q42.13ADCK3Px
SCAR103p22.1ANO10Px
SCAR111q32.2SYT14Px
SCAR1216q23.2WWOXPx
SCAR136q24.3GRM1Px
SCAR1411q13.2SPTBN2Px
SCAR153q29? RUBCNPx
SCAR1616p13.3STUB1Px
SCAR1710q24.31CWF19L1Px
SCAR184q22.1-q22.2GRID2Px
SCAR191p36.11? SLC9A1Px
SCAR206q14.3SNX14Px
SCAR2111q13.1SCYL1Px
SCAR222q11.2VWA3BPx
SCAR236p22.3TDP2Px
SCAR243q22.1UBA5Px
SCAR256q21? ATG5Px
SCAR2619q13.31? XRCC1Px
FRDA9q21.11FXNRE, P, Dxxx
VED8q12.3TTPAP, Dxx
SCAE15q26.1POLGP, Dxx
SCAN114q32.11TDP1Px
SCAN2see SCAR1
CAHH7p22.1RNF216Px
EAOH9p21.1APTXP, Dxx
IOSCA10q24.31C10orf2Px
SACS13q12.12SACSP, Dxx

Legend: RE: repeat expansion; P: punctiform (single nucleotide variations, small indels); D: large deletions or duplications; I: large insertion; FLA/RPA: fragment length analysis/repeat primed assay; Seq: sequencing; Del/dup: large deletions/duplications testing (MLPA/qPCR); the question point (?) indicates that the mutation has been detected in one single family or one single patient, so that the subtype needs to be confirmed.

Table 3 – X-linked spinocerebellar ataxias

SubtypeLocusGeneMutation spectrumRecommended testing
FLA/RPASeqDel/dup
SCAX1Xp11.21-q21.3ATP2B3Px
SCAX2unknownunknown
SCAX3unknownunknown
SCAX4unknownunknown
SCAX5Xq25-q27.1unknown
ASATXq13.3ABCB7Px
FXTASXq27.3FMR1REx

Legend: RE: repeat expansion; P: punctiform (single nucleotide variations, small indels); I: large insertion; FLA/RPA: fragment length analysis/repeat primed assay; Seq: sequencing.

Posted in Academia, Disease cards, Last Update, Medical Genetics and tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , .

Leave a Reply

Your email address will not be published. Required fields are marked *