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Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome
Percy ME, Potyomkina Z, Dalton AJ, Fedor B, Mehta P, Andrews DF, Mazzulli T, Murk L et al.. American journal of medical genetics. Part A, 2003-07-01
Topic: Brain proteins, microglia and lab models
Dementia of the Alzheimer type (DAT) is common in older persons with Down syndrome (DS). There are three common alleles of the apolipoprotein E (ApoE) gene (Sigma 2, Sigma 3, and Sigma 4) resulting in three different isoforms (E2, E3, and E4) and six different genotypes (2,2; 2,3; 2,4; 3,3; 3,4; and 4,4). Sigma 4 is a risk factor for DAT whereas Sigma 2 appears prophylactic. As hepatitis B virus (HBV) infection and hypothyroidism also are common in DS, we evaluated associations between ApoE type, HBV status, and thyroid status in a sample of older persons with DS (n = 55; mean age, 44.3 +/- 10.8 years) using chi-squared analysis. Participants were classified as E2 (2,2 or 2,3), E3 (3,3), or E4 (3,4 or 4,4); positive for markers of HBV infection in the present or past (i.e., total HBcAb+ and/or HBsAg+ with or without infectivity, defined as HBV+) or negative for markers of HBV infection (defined as HBV-) and, currently receiving thyroid hormone supplement (defined as "hypothyroidism") or having normal thyroid function. The majority of the HBV+ were currently HBcAb+ and HBsAb+, but not HBsAg+. In females, there was an ApoE allele effect on thyroid status (P < or = 0.01), E2 being negatively (P < or = 0.01) and E4 being positively (P < or = 0.05) associated with "hypothyroidism". There was no evidence for an ApoE allele effect on thyroid status in males. There was no evidence for an ApoE allele effect on HBV status, or for an HBV status effect on thyroid status. As thyroid status can affect cognitive function, ApoE allele effects in DAT may, in part, be thyroid effects.
Key findings
- In females, there was an ApoE allele effect on thyroid status (P < or = 0.01), E2 being negatively (P < or = 0.01) and E4 being positively (P < or = 0.05) associated with "hypothyroidism".
Why it matters
In 55 older people with Down syndrome, this study found an association in females between apolipoprotein E type and thyroid status, with E2 linked to lower and E4 to higher rates of hypothyroidism. It did not test any treatment or prevention for Alzheimer's disease.
Study details
- Participants55
- Effect sizeor = 0.01; or = 0.05
- Evidence strengthLow
How this study scored 40/100
Published in a peer-reviewed journal. Scored zero for study design and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (American journal of medical genetics. Part A) |
| Journal's citation record | 2 / 4 | American Journal of Medical Genetics Part A: journal h-index 161 (OpenAlex, 2026-10-29) |
| 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 | 2003 — older than 20 years, still counted |
| Sample size | 1 / 4 | 55 participants |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| 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 | 3 / 7 | Cited 20 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.8 citations a year over 25 year(s) since 2003 |
| Impact for its field and year | 1 / 6 | Cited 1.0× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 1 / 6 | Cited by 2 other studies in this library |
| Still being cited | 0 / 4 | Cited 1 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Linda Wu: h-index 23 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Johns Hopkins University: institution h-index 2,306 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 5 institution(s) in 3 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 12833399) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 40 / 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. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Percy, M. E., Potyomkina, Z., Dalton, A. J., Fedor, B., Mehta, P., Andrews, D. F., et al. (2003). Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome. American journal of medical genetics. Part A. https://doi.org/10.1002/ajmg.a.20099
Vancouver
Percy ME, Potyomkina Z, Dalton AJ, Fedor B, Mehta P, Andrews DF, et al. Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome. American journal of medical genetics. Part A. 2003. doi:10.1002/ajmg.a.20099. PMID: 12833399.
BibTeX
@article{percy2003-12833399,
author = {Percy, M. E. and Potyomkina, Z. and Dalton, A. J. and Fedor, B. and Mehta, P. and Andrews, D. F. and Mazzulli, T. and Murk, L. and others},
title = {{Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome}},
journal = {American journal of medical genetics. Part A},
year = {2003},
doi = {10.1002/ajmg.a.20099},
pmid = {12833399},
url = {https://doi.org/10.1002/ajmg.a.20099}
}
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