Evidence mapPaperPMID 40820147Full record

SynthesisScientific reports2025

Effects of the δ-aminolevulinic acid dehydratase polymorphism rs1800435 on blood lead levels: a new systematic review and meta-analysis.

Jiukun Jiang, Xiujing Xie

Abstract readMeta-AnalysisSystematic Review
In one paragraph

Synthesis in Scientific reports, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

2 authors.

Jiukun JiangEmergency Department, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou City, Zhejiang Province, China.
Xiujing XieDepartment of Ultrasound Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou City, Zhejiang Province, China. 1513003@zju.edu.cn.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Exposure to lead has various health effects. Studies have correlated the δ-aminolevulinic acid dehydratase (ALAD) polymorphism rs1800435 (ALAD1 and ALAD2) with blood lead levels, but the results have been inconsistent. This meta-analysis evaluated the associations between the rs1800435 and blood lead levels. Studies reporting the relationships of rs1800435 with blood lead levels were included. The sample size, means, and standard deviations were calculated. Subgroup analysis was performed on the basis of the presence or absence of lead exposure, age, sex, and geographic latitude of the investigated people. Twenty-seven studies with 17,344 individuals were included. There was no significant association between rs1800435 status and blood lead levels, either in the lead-exposed group (p = 0.280), nonlead-exposed group (p = 0.642), or overall analysis (p = 0.165). Among those exposed to lead, for people living at non-low latitudes (latitude > 30°), ALAD2 allele carriers had higher lead levels than ALAD1 homozygotes did (p = 0.001). For non-lead-exposed respondents, blood lead levels in male ALAD2 allele carriers demonstrated a marginally significant decrease compared with those in male ALAD1 homozygotes (p = 0.061). Lead exposure levels and the geographical latitude of long-term residence may modify the ALAD2-associated effects on blood lead concentrations.

Indexed as

LeadPolymorphism, Single NucleotidePorphobilinogen SynthaseAllelesFemaleHumansMaleLeadPorphobilinogen SynthaseLeadrs1800435Δ-aminolevulinic acid dehydratase polymorphism

Identifiers

PMID40820147
PMCPMC12358600

What Socratic holds

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Registered trials

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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 Socratic graph.