Læknablaðið

Ukioqatigiit

Læknablaðið - 15.10.1997, Qupperneq 33

Læknablaðið - 15.10.1997, Qupperneq 33
LÆKNABLAÐIÐ 1997; 83 655 Erfðafræði Alzheimers sjúkdóms Gísli Ragnarsson Ragnarsson G The Genetics of Alzheimer’s Disease Læknablaðið 1997; 83: 655-63 The aetiology of Alzheimer’s disease (AD) is still unknown, but a small fraction of AD patients have a dominant inherited defect in one of three genes. These patients often develop Alzheimer’s disease between 40 to 65 years of age. The majority of patients, however, get the disease after the age of 65 and do not have a gene defect in any of these three genes. Apart from age of onset, no symptomatic or pathological difference exists between AD patients with or without known genetic defect. In patients with AD before the age of 65 a germ-line gene defect in the APP gene ((S-amyloid precursor protein) at chromosome 21q21.2, the PS-1 gene (pre- senilin) at chromosome 14q24.3 and the PS-2 gene at chromosome lq42.1 has been identified. The first mutation was discovered 1991 in the APP gene in a family with early-onset AD. Since then hundreds of families have been screened for mutations in this gene but they have only been found in 10 to 15 families. On the other hand more than 35 different mutations in over 60 unrelated families have been discovered in the PS-1 gene and nearly half of AD patients with familial early-onset AD have muta- tions in this gene. Patients with mutation in the PS-1 gene often get AD before the age of 50 and even before the age of 40. The third germ line gene defect was discovered 1995 in the PS-2 gene by screening the genome in search for PS-1 gene homology. Two different mutations have been found in PS-2 gene in unrelated families. Fyrirspurnir, bréfaskipti: Gísli Ragnarsson, frumulíffræði- deild Rannsóknastofu Háskóla Islands I meinafræði, Land- spítalanum, 101 Reykjavík. Sími: 560 1906; netfang: gislira@rsp.is Lykilorð: Alzheimers sjúkdómur, [S-amýloid-forveraprótín, presenilin-1, presenilin-2, apólípóprótín E-4. An increased risk of late-onset AD has been asso- ciated with apolipoprotein E (ApoE). ApoE exists in three different isoforms: ApoE2, ApoE3 and ApoE4. Three alleles (e2, e3, and e4) on chromo- some 19ql3.2 encode these different kinds of ApoE. Those who are e4 homozygous (e4/e4) have in- creased risk of late-onset AD, and usually develop symptoms earlier in live than e4 negatives. The same applies to e4 heterozygous (e3/e4 or e2/e4) individu- als even though their risk does not increase as much as e4 homozygous. Other chromosome regions have been linked to late-onset AD, an example is a region on chromo- some 12. Furthermore mutations in the mitochon- drial genes that encode the enzyme cytochrome c oxidase have also recently been shown to be associ- ated with AD. Correspondence: Gísli Ragnarsson, Laboratory of Cell Biology, Dpt. of Pathology, Landspítalinn, 101 Reykjavík, lceland. Telephone: (354) 560 1906; e-mail: gislira@rsp.is Key words: Alzheimer's disease, fi-amyloid-precursorpro- tein, Presenilin-1, Presenilin-2, apolipoprotein E-4. Ágrip Orsakir Alzheimers sjúkdóms eru ekki þekktar, en vitað er að nokkur hluti Alzheim- ers sjúklinga er með ríkjandi erfðagalla í ein- hverju af þremur genum með nær 100% sýnd. Þessir sjúklingar fá sjúkdóminn yfirleitt á aldr- inum 40 til 65 ára. Flestir sjúklingar með AI- zheimers sjúkdóm greinast eftir 65 ára aldur og hafa ekki galla í þessum genum. Ekki er munur á meingerð Alzheimers sjúkdóms hjá sjúkling- um með þekkta genagalla og þeim sem ekki hafa slíka galla. Margir sem greinast með Alzheimers sjúk- dóm fyrir 65 ára aldur hafa kímlínugenagalla í APP (þ-amyloid precursor protein, App) geni á litningi 21q21.2, PS-1 (presenilin, Ps) geni á litningi 14q24.3 eða PS-2 geni á litningi lq42.1.
Qupperneq 1
Qupperneq 2
Qupperneq 3
Qupperneq 4
Qupperneq 5
Qupperneq 6
Qupperneq 7
Qupperneq 8
Qupperneq 9
Qupperneq 10
Qupperneq 11
Qupperneq 12
Qupperneq 13
Qupperneq 14
Qupperneq 15
Qupperneq 16
Qupperneq 17
Qupperneq 18
Qupperneq 19
Qupperneq 20
Qupperneq 21
Qupperneq 22
Qupperneq 23
Qupperneq 24
Qupperneq 25
Qupperneq 26
Qupperneq 27
Qupperneq 28
Qupperneq 29
Qupperneq 30
Qupperneq 31
Qupperneq 32
Qupperneq 33
Qupperneq 34
Qupperneq 35
Qupperneq 36
Qupperneq 37
Qupperneq 38
Qupperneq 39
Qupperneq 40
Qupperneq 41
Qupperneq 42
Qupperneq 43
Qupperneq 44
Qupperneq 45
Qupperneq 46
Qupperneq 47
Qupperneq 48
Qupperneq 49
Qupperneq 50
Qupperneq 51
Qupperneq 52
Qupperneq 53
Qupperneq 54
Qupperneq 55
Qupperneq 56
Qupperneq 57
Qupperneq 58
Qupperneq 59
Qupperneq 60
Qupperneq 61
Qupperneq 62
Qupperneq 63
Qupperneq 64
Qupperneq 65
Qupperneq 66
Qupperneq 67
Qupperneq 68
Qupperneq 69
Qupperneq 70
Qupperneq 71
Qupperneq 72
Qupperneq 73
Qupperneq 74
Qupperneq 75
Qupperneq 76
Qupperneq 77
Qupperneq 78
Qupperneq 79
Qupperneq 80
Qupperneq 81
Qupperneq 82
Qupperneq 83
Qupperneq 84
Qupperneq 85
Qupperneq 86
Qupperneq 87
Qupperneq 88
Qupperneq 89
Qupperneq 90
Qupperneq 91
Qupperneq 92
Qupperneq 93
Qupperneq 94
Qupperneq 95
Qupperneq 96
Qupperneq 97
Qupperneq 98
Qupperneq 99
Qupperneq 100

x

Læknablaðið

Direct Links

Hvis du vil linke til denne avis/magasin, skal du bruge disse links:

Link til denne avis/magasin: Læknablaðið
https://timarit.is/publication/986

Link til dette eksemplar:

Link til denne side:

Link til denne artikel:

Venligst ikke link direkte til billeder eller PDfs på Timarit.is, da sådanne webadresser kan ændres uden advarsel. Brug venligst de angivne webadresser for at linke til sitet.