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40/100

✓ Peer-reviewed alzhub usefulness score 40 out of 100. Down syndrome and Alzheimer's

Topic: Brain proteins, microglia and lab models

Chromosome 21-specific yeast artificial chromosomes (YACs) have been constructed by a method that performs all steps in agarose, allowing size selection by pulsed-field gel electrophoresis and the use of nanogram to microgram quantities of DNA. The DNA sources used were hybrid cell line WAV-17, containing chromosome 21 as the only human chromosome and flow-sorted chromosome 21. The transformation efficiency of ligation products was similar to that obtained in aqueous transformations and yielded YACs with sizes ranging from 100 kilobases (kb) to greater than 1 megabase when polyamines were included in the transformation procedure. Twenty-five YACs containing human DNA have been obtained from a mouse-human hybrid, ranging in size from 200 to greater than 1000 kb, with an average size of 410 kb. Ten of these YACs were localized to subregions of chromosome 21 by hybridization of RNA probes (corresponding to the YAC ends recovered in Escherichia coli) to a panel of somatic cell hybrid DNA. Twenty-one human YACs, ranging in size from 100 to 500 kb, with an average size of 150 kb, were obtained from approximately equal to 50 ng of flow-sorted chromosome 21 DNA. Three were localized to subregions of chromosome 21. YACs will aid the construction of a physical map of human chromosome 21 and the study of disorders associated with chromosome 21 such as Alzheimer disease and Down syndrome.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

McCormick, M. K., Shero, J. H., Cheung, M. C., Kan, Y. W., Hieter, P. A., & Antonarakis, S. E. (1989). Construction of human chromosome 21-specific yeast artificial chromosomes. Proceedings of the National Academy of Sciences of the United States of America. https://doi.org/10.1073/pnas.86.24.9991

Vancouver

McCormick MK, Shero JH, Cheung MC, Kan YW, Hieter PA, Antonarakis SE. Construction of human chromosome 21-specific yeast artificial chromosomes. Proceedings of the National Academy of Sciences of the United States of America. 1989. doi:10.1073/pnas.86.24.9991. PMID: 2690083.

BibTeX

@article{mccormick1989-2690083,
  author  = {McCormick, M. K. and Shero, J. H. and Cheung, M. C. and Kan, Y. W. and Hieter, P. A. and Antonarakis, S. E.},
  title   = {{Construction of human chromosome 21-specific yeast artificial chromosomes}},
  journal = {Proceedings of the National Academy of Sciences of the United States of America},
  year    = {1989},
  doi     = {10.1073/pnas.86.24.9991},
  pmid    = {2690083},
  url     = {https://doi.org/10.1073/pnas.86.24.9991}
}

Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.

Key findings

YACs will aid the construction of a physical map of human chromosome 21 and the study of disorders associated with chromosome 21 such as Alzheimer disease and Down syndrome.

Why it matters

This work built tools to map chromosome 21, the chromosome linked to Alzheimer disease and Down syndrome. It does not test any treatment, cure, or prevention; it is an early laboratory step toward studying these disorders.

Study details

Evidence strengthLow

How this study scored 40/100

Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported and randomised / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Proceedings of the National Academy of Sciences of the United States of America)
Journal's citation record	4 / 4	Proceedings of the National Academy of Sciences: journal h-index 1,167 (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	1989 — older than 20 years, still counted
Sample size	0 / 4	Participant count not stated — scores zero (not stated in the record — scored 0)
Effect reported	0 / 3	No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people	0 / 3	Laboratory or animal study (title names “yeast”) — scores zero
Randomised / blinded	0 / 2	No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited	4 / 7	Cited 70 times (OpenAlex, 2026-10-10)
Citations per year	1 / 5	1.8 citations a year over 39 year(s) since 1989
Impact for its field and year	3 / 6	Cited 7.5× 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 / 4	Last-listed author Stylianos E. Antonarakis: h-index 146 (OpenAlex, whole career)
Institution's track record	2 / 3	Johns Hopkins University: institution h-index 2,306 (OpenAlex)
Multi-centre collaboration	1 / 3	OpenAlex lists 2 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 2690083)
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 →

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