Evidence map›Paper›PMID 30204801›Full record

Trial reportPloS one2018

Females of HbAS genotype have reduced concentration of the malaria protective deoxyhemoglobin S than males.

John N Waitumbi, Carolyne M Kifude, Carol W Hunja, Bernhards R Ogutu

Open access · goldAbstract readClinical Trial, Phase IIMulticenter Study
In one paragraph

Trial report in PloS one, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact, top 87% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed, 2 citations in OpenAlex.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 2 institutions in 1 country.

John N WaitumbiWalter Reed Project, Kenya Medical Research Institute, Kisumu, Kenya.ORCID 0000-0003-2540-4397
Carolyne M KifudeWalter Reed Project, Kenya Medical Research Institute, Kisumu, Kenya.
Carol W HunjaSouth Eastern Kenya University, School of Pure and Applied Sciences, Department of Biology, Kitui, Kenya.
Bernhards R OgutuWalter Reed Project, Kenya Medical Research Institute, Kisumu, Kenya.
Kenya Medical Research Institute · KESouth Eastern Kenya University · KE

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The quantity of the intra-erythrocytic deoxyhemoglobin S (Hb S) affects the level of protection against malaria and also the sickling phenomenon. This study reports on significantly lower concentration of Hb S in females than males. Data came from 350 children, aged 12-47 months who participated in a phase 2b malaria vaccine trial. Hemoglobinopathy and G6PD deficiency typing was necessary to ascertain equal representation of these malaria protective traits across the vaccine cohorts. Hemoglobin types (HbAA, HbAS) and % Hb S were evaluated by HPLC. Alpha thalassemia (alpha-thal) and G6PD genotypes were evaluated by PCR. The overall prevalence for HbAS was 20%, 46% for 3 alpha genes and 10% for 2 alpha genes and 14% for G6PD A-. More females of HbAS/αα/αα genotype had low Hb S than males and had mean % Hb S of 37.5% ± 5.4 SD, compared to 42.0% ± 2.5 SD in males of same genotype (P = 0.018). Consistent with reduction of the malaria protective Hb S in females, parasite load in females was nearly twice that of males but the difference was not statistically significant. The X-chromosome linked G6PD deficiency did not influence the level of Hb S. We conclude that, the low Hb S in these females explains the resultant higher malaria parasite load. We speculate that the low Hb S in females could also explain observations suggesting that the sickling phenomenon tends to be less severe in females than males.

Indexed as

GenotypeMalariaSex Characteristicsalpha-ThalassemiaChild, PreschoolFemaleGlucosephosphate Dehydrogenase DeficiencyHemoglobinsHemoglobin, SickleHumansInfantMalaria VaccinesMaledeoxyhemoglobinHemoglobinsHemoglobin, SickleMalaria Vaccines

Identifiers

PMID30204801
PMCPMC6133351
OpenAlexW2890845148

What OpenQuestion holds

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LicenceCC0
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.