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[The apolipoprotein E genotype and Down's syndrome]
Rascón Trincado MV, González Sarmiento R, Salazar A-Villalobos V.. Revista clinica espanola, 1997-10-01
Topic: Brain proteins, microglia and lab models
Some individuals with Down syndrome develop an Alzheimer-type dementia in the third and fourth decades of life. Dementia in Alzheimer disease has been associated with the presence of genotype epsilon 4/epsilon 4 in apolipoprotein E (apo E). By means of molecular analysis techniques genotypes in lipoprotein apo E were identified in 21 patients with Down syndrome. The results obtained showed that 76% of the studied population had the genotype epsilon 3/epsilon 3 and 9% genotypes epsilon 3/epsilon 4 and epsilon 2/epsilon 3. None of the cases was homozygous for the allele epsilon 4. The analysis of our data shows the absence of differences between the distribution of genotype apo E among the Down population studied and among general population. We therefore consider that the presence of the allele epsilon 4 has no influence on the manifestation of Alzheimer disease in patients with Down syndrome.
Key findings
- Dementia in Alzheimer disease has been associated with the presence of genotype epsilon 4/epsilon 4 in apolipoprotein E (apo E).
- The results obtained showed that 76% of the studied population had the genotype epsilon 3/epsilon 3 and 9% genotypes epsilon 3/epsilon 4 and epsilon 2/epsilon 3.
Why it matters
In 21 patients with Down syndrome, this study found no difference in apolipoprotein E genotype distribution compared with the general population. It concluded that the epsilon 4 allele had no influence on the appearance of Alzheimer disease in these patients, so it reports no treatment, cure or prevention.
Study details
- Participants21
- Evidence strengthLow
How this study scored 27/100
Published in a peer-reviewed journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it. We have no data on journal's citation record and senior author's track record, so those were left out: it earned 25 of the 92 points we could judge it on, which is 27 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Revista clinica espanola) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1997 — older than 20 years, still counted |
| Sample size | 1 / 4 | 21 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 0 / 7 | Cited 0 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.0 citations a year over 31 year(s) since 1997 |
| Impact for its field and year | 0 / 6 | Cited 0.0× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 0 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | — / 4 | OpenAlex's profile for last-listed author V Salazar A-Villalobos holds only 6 work(s), too few to judge a track record — left out of this score |
| Institution's track record | 0 / 3 | Universidad de Salamanca: institution h-index 432 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9424665) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 25 / 92 | Scored on 18 of 20 parts. We have no data for the rest, so they are left out: 25 of the 92 points we could judge it on is 27 out of 100. |
| Total | 27 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. This record has no DOI, so the citation leaves it out. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Rascón Trincado, M. V., González Sarmiento, R., & Salazar A-Villalobos, V. (1997). [The apolipoprotein E genotype and Down's syndrome]. Revista clinica espanola.
Vancouver
Rascón Trincado MV, González Sarmiento R, Salazar A-Villalobos V. [The apolipoprotein E genotype and Down's syndrome]. Revista clinica espanola. 1997. PMID: 9424665.
BibTeX
@article{rascontrincado1997-9424665,
author = {Rascón Trincado, M. V. and González Sarmiento, R. and Salazar A-Villalobos, V.},
title = {{[The apolipoprotein E genotype and Down's syndrome]}},
journal = {Revista clinica espanola},
year = {1997},
pmid = {9424665}
}
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