zinc superoxide dismutase (SOD1) gene mutations

zinc superoxide dismutase (SOD1) gene mutations

Neuromuscular Disorders 10 (2000) 63±68 www.elsevier.com/locate/nmd Amyotrophic lateral sclerosis: copper/zinc superoxide dismutase (SOD1) gene mutat...

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Neuromuscular Disorders 10 (2000) 63±68 www.elsevier.com/locate/nmd

Amyotrophic lateral sclerosis: copper/zinc superoxide dismutase (SOD1) gene mutations Richard W. Orrell* University Department of Clinical Neurosciences, Royal Free and University College Medical School, Rowland Hill Street, London NW3 2PF, UK Received 16 June 1999; accepted 1 July 1999

Abstract Mutations of the SOD1 gene, encoding the enzyme copper/zinc superoxide dismutase, have been identi®ed in around 20% of patients with familial amyotrophic lateral sclerosis (ALS), and also in patients with apparently sporadic ALS. The table documents the mutations identi®ed and published to date, and references clinical and pathological descriptions of the patients and families with individual mutations. The table includes 63 different mutations of SOD1 at 43 codons, three intronic sites, and two in the 3 0 untranslated region. Most of the mutations are heterozygotes, with autosomal dominant inheritance, but a small number of individuals appear to be sporadic, or are homozygotes with autosomal dominant recessive inheritance. q 2000 Elsevier Science B.V. All rights reserved. Keywords: Amyotrophic lateral sclerosis; SOD1; Genetics

1. Introduction Mutations of the SOD1 gene in amyotrophic lateral sclerosis (ALS) were ®rst identi®ed by Rosen et al. [47]. Around 5±10% of patients with ALS have other affected family members, and mutations of SOD1 are present in around 20% of these familial patients, and also in occasional apparently sporadic patients. This represents only 1±2% of all patients with ALS. A causal relationship has not been demonstrated for all the mutations reported, and the mechanism by which the mutations cause the disease has still to be clari®ed. Many of the mutations are at present unique to individual families. Reports of attempts to correlate genotype with phenotype have demonstrated that, for an individual, the severity of disease, as determined by time of onset or duration of disease, is generally dif®cult to predict on the basis of the SOD1 mutation [4,9,42]. Some mutations, however, appear to predict a more rapid course of disease, for example, Ala4Val, (which accounts for around 50% of mutations reported in the USA [9]). In Scandinavia, the ®nding of a homozygote form of the disease, also appears to have an Asp90A1a de®nable phenotype [3]. Otherwise in general the prognosis is similar to that of ALS in general, with median age at onset 46 years (range 24±72 years), and median duration of disease 3.0 years (range 0.3±20 years) * Tel.: 144-171-830-2387; fax: 144-171-431-1577. E-mail address: [email protected] (R.W. Orrell)

[42]. Penetrance is age dependent, and in families with autosomal dominant inheritance of the mutation, the disease may appear to skip several generations [40]. The clinical features of an individual patient with an SOD1 mutation are indistinguishable from those without an SOD1 mutation, although there is a tendency for the disease to commence in the limbs rather than the bulbar region. Molecular pathological studies may be expected to yield more detailed information on the pathogenesis of the disease. The reported number of patients is small. The pathology of ALS patients with SOD1 mutations has recently been investigated and reviewed by Ince et al. [21], focusing on the nature of neuronal inclusions, the signi®cance of which remains uncertain. The disease appears not to be caused by loss of SOD enzyme activity, but by gain of an as yet unknown toxic function, consistent with the predominant autosomal dominant pattern of inheritance. The major gene abnormalities in the other 80% of families with ALS, and the genetic contribution to the remainder of apparently sporadic ALS, representing around 98% of all patients with ALS, remain unknown. These are being explored by clinical molecular genetic studies, molecular pathological studies, studies of SOD1 patients and families, and studies of transgenic mouse models incorporating mutations of SOD1 found in human ALS. Linkage studies in both recessive and dominant forms of ALS have de®ned linkage in the recessive forms, e.g. ALS2 at 2q33

0960-8966/00/$ - see front matter q 2000 Elsevier Science B.V. All rights reserved. PII: S 0960-896 6(99)00071-1

GCC ! ACC

4

Leu-Phe Leu ! Val

TTG ! TTC TTG ! GTG

GGC -CGC AAT ! AGT GAC ! GCC

GAC ! GTC GGT ! AGT

85 86 90

90 93

Asp ! Val Gly ! Ser

Gly ! Arg Asn ! Ser Asp ! Ala

Asp ! Tyr

Gly ! Ser

GGT ! AGT

GAT ! TAT

Gly ! Asp His ! Arg His ! Arg His ! Gln

GGC ! GAC CAT ! CGT CAT ! CGT CAT ! CAG

76 Exon 4 84 84

41 43 46 48 Exon 3 72

s/m s/m

s/m s/m s/m

s/m s/m

s/m

s/m

s/m s/m s/m s/m

s/m s/m s/m

Gly ! Arg Leu ! Val Gly ! Ser

GGA ! AGA CTG ! GTG GGC ! AGC

s/m s/m s/m s/m s/m s/m s/m s/m

s/m

s/m

Nature /effect of mutation

s/u

Cys ! Phe Val ! Glu Leu ! Gln Val ! Met Val ! Gly Gly ! Ser Glu ! Lys Glu ! Gly

Ala ! Thr

Ala ! Val

Amino acid change

T!A

TGC ! TTT GTG ! GAG CTG ! CAG GTG ! ATG GTG ! GGG GGC ! AGC GAG ! AAG GAG ! GGG

GCC ! GTC

Exon 1 4

6 7 8 14 14 16 21 21 Intron 1 2108 bp Exon 2 37 38 41

Base change

Codon

Table 1 Gene table

AD AD AD AD AD AD Homo AD and S Homo AR and S Homo AD and S Homo S S AD AD

AD AD AD

AD AD AD AD AD AD AD AD

S

1 1 1 1 1 1 2 and 1 9 and 7 1 and 3 2 1 1 1

1 1 1

1 2 1 1 1 1 2 1

1

1 1 1 1 1 1 1 1

1 2

AD AD AD AD AD AD AD S S AD

27

Number of families reported

AD

Inheritance

UK USA Japan Japan USA Pakistan Belgium Sweden/Finland Sweden/Finland Finland UK Japan Japan

UK UK Denmark

USA USA USA Italy USA USA Japan UK

UK

Japan Japan Austria USA Sweden Japan UK France

Sweden Japan

USA

Country

C C C C

C C C

C C

C

C C C

C C C C C C C CP

CP

C C

C P C C P C C C

Clinical or pathological description

Shaw et al. (1998) Deng et al. (1995) Ohnishi et al. (1996) Aoki et al. (1995) Deng et al. (1993) Hayward et al. (1998) Robberecht et al. (1996) Andersen et al. (1996) Andersen et al. (1997) Andersen et al. (1997) Jackson et al. (1997) Morita et al. (1998) Kawata et al. (1997)

Orrell et al. (1997a) Shaw et al. (1998) Andersen et al. (1997)

Cudkowicz et al. (1997) Cudkowicz et al. (1997) Cudkowicz et al. (1997) Rainero et al. (1994) Cudkowicz et al. (1997) Cudkowicz et al. (1997) Abe et al. (1996) Shaw et al. (1996)

Ince et al. (1998)

Cudkowicz et al. (1997) Cudkowicz et al. (1998) Andersen et al. (1997) Nakano et al. (1994) Takahashi et al. (1994) Morita et al. (1996) Hirano et al. (1994) Bereznai et al. (1997) Deng et al. (1995) Andersen et al. (1997) Kawamata et al. (1997) Jones et al. (1995) Moulard et al. (1995)

Reference

[49] [11] [37] [5] [10] [15] [46] [3] [4] [4] [22] [34] [28]

[41] [49] [4]

[9] [9] [9] [45] [9] [9] [1] [50]

[21]

[9] [8] [4] [36] [53] [33] [17] [6] [11] [4] [26] [23] [35]

Ref no.

64 R.W. Orrell / Neuromuscular Disorders 10 (2000) 63±68

Asp ! Val Asp ! His Leu ! Gly, Gln, Arg, Trp, Lys, Stop Gly ! Gly, Gly, Gln, Arg, Trp, Lys, Stop Glu ! Asp, Stop Glu ! ± Ser ! Asn Asn ! Lys Leu ! Ser

CGC ! GGC GTG ! AAAACTG

A!G

GAT ! GTT GAC ! CAC TTC ! ±G

115 118

ins TGGG

insTT GAA ! ± AGT ! AAT AAC ! AAA TTG ! TCG

127

132 133 134 139 144

2 10 bp Exon 5 124 125 126

T!G

add Phe, Phe, Thr, s/it Gly, Pro, Stop add Phe, Leu, Gln s/i

GGA ! GTA ATC ! ACC ATT ! ACT

108 112 113

Intron 4 2 11 bp

Arg ! Gly Val ! Lys, Thr, Gly, Pro, Stop

GAT ! AAT GAT ! GGT ATC ! TTC CTC ! GTC

Gly ! Val Ile ! Thr Ile ! Thr

Asp ! Asn Asp ! Gly Ile ! Phe Leu -Val

i/mt d/d s/m s/m s/m

i/it

s/m s/m d/it

s/m i/it

s/m s/m s/m

s/m s/m s/m s/m

s/m s/m s/m s/m s/m s/m s/m

101 101 104 106

Gly ! Cys Gly ! Arg Gly ! Asp Gly ! Ala Gly ! Val Glu ! Lys Glu ! Gly

GGT ! TGT GGT ! CGT GGT ! GAT GGT ! GCT GGT ! GTT GAA ! AAA GAA -GGA

Nature /effect of mutation

93 93 93 93 93 100 100

Amino acid change

Base change

Codon

Table 1 (continued)

AD S AD AD AD

AD

AD AD AD

1 1 1 1 1

1

1 1 1

1

2 1 3 1 1 1 1 1 1 1 1 2 1 1 1 1 and 1 1 and 1 2 1 1

AD AD AD AD AD AD AD AD AD AD AD AD AD AD AD AD and S AD and S S AD S

AD

1 1 1 1 1

Number of families reported

AD AD AD AD AD

Inheritance

UK USA Japan Canada USA

Denmark

USA UK Japan

USA

USA New Zealand UK UK UK UK Japan USA Japan UK USA USA Australia UK Canada Japan UK UK Germany UK

USA UK USA USA UK

Country

C

C C C

C

C C CP

C

C C C CP C C C C C C C C C CP CP CP CP C C C

C C C C C

Clinical or pathological description

Orrell et al. (1997b) Hosler et al. (1996) Watanabe et al. (1997) Pramatarova et al. (1995) Cudkowicz et al. (1997)

Andersen et al. (1997)

Hosler et al. (1996) Enayat et al. (1995) Kato et al. (1996)

Cudkowicz et al. (1997)

Siddique and Deng (1996)

Cudkowicz et al. (1997) Orrell et al. (1995a) Cudkowicz et al. (1997) Cudkowicz et al. (1997) Hosler et al. (1996) Siddique and Deng (1996) Cudkowicz et al. (1997) Calder et al. (1995) Orrell et al. (1997b) Ince et al. (1996) Orrell et al. (1996) Orrell et al. (1997b) Abe et al. (1996) Cudkowicz et al. (1997) Kawamata et al. (1994) Orrell et al. (1997c) Cudkowicz et al. (1997) Cudkowicz et al. (1997) Suthers et al. (1994) Orrell et al. (1995b) Rouleau et al. (1996) Kikugawa et al. (1997) Ince et al. (1998) Jackson et al. (1997) Kostrzewa et al. (1994) Jackson et al. (1997)

Reference

[42] [18] [54] [44] [9]

[4]

[18] [12] [24]

[9]

[51]

[9] [38] [9] [9] [18] [51] [9] [7] [42] [20] [20] [42] [1] [9] [25] [43] [9] [9] [52] [39] [48] [29] [21] [22] [30] [22]

Ref no.

R.W. Orrell / Neuromuscular Disorders 10 (2000) 63±68 65

TTG ! TTC GCT ! ACT TGT-CGT GTA ! GGA GTA ! ATA ATT ! ACT

ACC ! ATC

144 145 146 148 148 149

151 3 0 UTR bp726 bp 816±819

Variants Exon 1 10 Exon 3 59 Exon 5 139 140 153

Gly ! Gly

Ser ! Ser

Asn ! Asn Ala ! Ala Gln ! Gln

ACT ! AGC

AAC ! AAT GCT ! GCA CAA ! CAG

Thr ! Ile

Leu ! Phe Ala ! Thr Cys ! Arg Val ! Gly Val ! Ile Ile ! Thr

Amino acid change

GGC ! GGT

Polymorphisms Intron 2 Unknown Bgl II Intron 3 34 A!C

Deleted Deleted

Base change

Codon

Table 1 (continued)

d/u d/u

s/m

s/m s/m s/m s/m s/m s/m

Nature /effect of mutation

S

S

S S

AD

AD AD AD AD AD AD

Inheritance

1 1 1

1

1

1 1

1 1 1 1 1 1 1 1

Number of families reported

Scandinavia USA Scandinavia

USA

UK

UK UK

Canada USA Japan USA Japan Canada UK Germany

Country

CP CP

C C

C C

C

Clinical or pathological description

Andersen et al. (1997) Hosler et al. (1996) Andersen et al. (1997)

Hosler et al. (1996)

[4] [18] [4]

[18]

[22]

[13]

Esteban et al. (1994)

Jackson et al. (1997)

[32]

[21] [21]

[44] [9] [27] [9] [1] [44] [42] [31]

Ref no.

Levanon et al. (1985)

Ince et al. (1998) Ince et al. (1998)

Pramatarova et al. (1995) Cudkowicz et al. (1997) Kawamata et al. (1995) Cudkowicz et al. (1997) Abe et al. (1996) Pramatarova et al. (1995) Orrell et al. (1997b) Kostrzewa et al. (1996)

Reference

66 R.W. Orrell / Neuromuscular Disorders 10 (2000) 63±68

R.W. Orrell / Neuromuscular Disorders 10 (2000) 63±68

[19] and ALS5 at 15q15-22 [16]. Variants of the gene encoding the heavy neuro®lament subunit have been identi®ed in a small number of patients [2,14]. The SOD1 gene has 5 exons, and encodes a protein with 153 amino acids [32]. The active enzyme is homodimeric. Table 1 includes 63 different mutations of SOD1 at 43 codons, three intronic sites, and two in the 3 0 untranslated region (UTR). Most of the mutations are heterozygote, with autosomal dominant inheritance (AD), but a small number of individuals appear to be sporadic (S), or are homozygote (Homo) with autosomal recessive inheritance (AR). 2. Footnotes Table 1 includes key references, which especially relate to reports which include details of the clinical (C) or pathological (P) features of the patients. Many of the mutations were ®rst reported by Rosen et al. [47] and Deng et al. [10], but clinical details were not given at that time. The number of families reported is given where available, as an indication of the relative frequency of the mutations. The country of origin of the patient, or report, is given. This does not necessarily indicate the true frequency, country of origin, or ethnicity of the patient. The nature of the mutation ± base substitution (s), base insertion (i), base deletion (d), and predicted result of mutation ± missense/amino acid substitution (m), uncertain or unknown (u), amino acid insertion (i), and premature termination of protein (t). References [1] Abe K, Aoki M, Ikeda M, Watanabe M, Hirai S, Itoyama Y. Clinical characteristics of familial amyotrophic lateral sclerosis with Cu/Zn superoxide dismutase gene mutations. J Neurol Sci 1996;136:101± 108. [2] Al-Chalabi A, Andersen PM, Nilsson P, et al. Deletions of the heavy neuro®lament subunit tail in amyotrophic lateral sclerosis. Hum Mol Genet 1999;8:157±164. [3] Andersen PM, Forsgren L, Binzer M, et al. Autosomal recessive adult-onset amyotrophic lateral sclerosis associated with homozygosity for Asp90Ala CuZn-superoxide dismutase mutation. Brain 1996;119:1153±1172. [4] Andersen PM, Nilsson P, Keranen ML, et al. Phenotypic heterogeneity in motor neuron disease patients with CuZn-superoxide dismutase mutations in Scandinavia. Brain 1997;120:1723±1737. [5] Aoki M, Abe K, Houi K, et al. Variance of age at onset in a Japanese family with amyotrophic lateral sclerosis associated with a novel Cu/ Zn superoxide dismutase mutation. Ann Neurol 1995;37:676±679. [6] Bereznai B, Winkler A, Borasio GD, Gasser T. A novel SOD1 mutation in an Austrian family with amyotrophic lateral sclerosis. Neuromusc Disord 1997;7:113±116. [7] Calder VL, Domigan NM, George PM, Donaldson IM, Winterbourn CC. Superoxide dismutase (glu100gly) in a family with inherited motor neuron disease: detection of mutant superoxide dismutase activity and the presence of heterodimers. Neurosci Lett 1995;189:143±146. [8] Cudkowicz ME, McKennar-Yasek D, Chen C, Hedley-Whyte ET, Brown RH. Limited corticospinal tract involvement in amyotrophic lateral sclerosis subjects with the A4V mutation in the copper/zinc dismutase gene. Ann Neurol 1998;43:703±710.

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