Table 1:
Overview of genetic testing for neurodegenerative diseases
| Typical age of onset | Population risks | Inheritance | Genes tested (chromosome) | DTC testing available?1 | Sources | |
|---|---|---|---|---|---|---|
| Juvenile onset: <20 yrs (5–10% of cases) Adult onset mean age: 35 to 44 yrs |
Varies across world regions European ancestry: 9.71 per 100,000 East Asia, Finland, indigenous South Africans: 0.1 to 2 per 100,000 |
Autosomal dominant | CAG trinucleotide repeat expansion in the HTT gene (4p16.3) | No | PMID: 20301482 GTR Test ID: GTR000502937.4 | |
| Early onset: age <60–65yrs (5% of cases) Late onset: age >60–65yrs (95% of cases) |
General population: 10–15% Lifetime risk to first degree family members with late onset AD: 15–25% |
25% of all AD is familial Early onset familial AD: autosomal dominant |
Early-onset autosomal dominant AD: APP (21 q21.3), PSEN1 (14q24.2), PSEN2 (1 q42.13) Risk allele for later-onset AD: APOE (19q13.32) |
Yes, for APOE | PMID: 20301340 GTR Test ID: GTR000505595.2 | |
| Lewy Body | 50–85 yrs | 3.5 per 100,000 person years | Autosomal dominant | APOE (19q13.32) GBA (1q22) SNCA (4q22.1) | No | MedGen UID: 199874 PMID: 2404291 |
| Frontotemporal Dementia | 40–60 yrs | About 20–50% of persons with FTD have a positive family history | Autosomal dominant | Multigene panel that typically includes: MAPT (17q21.31) GRN (17q21.31) C9orf72 (9p21.2) | No | PMID: 20301678 PMID: 20301545 |
| Juvenile onset: <20 years Early onset: 2050 yrs Adult onset: >50 yrs Typically, around 60 yrs |
General population: 4% First degree relatives: 8% | Autosomal dominant; Autosomal recessive | Multi-gene panels; In families with autosomal dominant inheritance: GBA (1q22), LRRK2 (12q12), SNCA, VPS35 In families with autosomal recessive inheritance: ATP13A2, DJ1, DNAJC6, FBXO7, PINK1, PODXL, PRKN, SLC6A3, SYNJ1, VPS13C |
Yes; for LRRK2 and GBA | PMID: 20301402 GTR Test ID: GTR000552609.1 | |
| Mean age males: 55 years Mean age females: mid60s Individuals with familial ALS tend to have an earlier onset of symptoms |
Males are more affected than females in 1.3/1 ratio | Autosomal dominant; Autosomal recessive; X-linked 10–15% of individuals with ALS have an inherited form |
Multigene panel that typically includes: C9orf72 (9p21.2), SOD1 (21q22.11), FUS (16p11.2), TARDBP (1p36.22) | No | PMID: 20301623 GTR Test ID: GTR000551921.12 | |
| Familial Creutzfeldt-Jakob disease: typically 30–50 yrs Germann- Staussuler- Scheinker syndrome: 30–50yrs Fatal familial insomnia: 40–50yrs |
Worldwide yearly incidence of genetic and non-genetic prion disease: 1–1.5 cases per million | Autosomal dominant | PNRP (20p13) | No. | PMID: 20301407 GTR Test ID: GT R000566062. 1 |