marklar@dna:~$ explore --locus rs671
Open Research Tool • Local In-Browser Processing

Did your standard DNA test account for East Asian metabolic baselines?

Genomic research has historically overrepresented European ancestry.[1] Explore a pathway that deserves regional context: ALDH2 (rs671), involved in acetaldehyde clearance and the cellular response to reactive aldehydes.

No raw DNA uploadsNo account requiredOpen source
LOCUS / 12q24.12ALDH2
G > ASCHEMATIC · NOT TO SCALE
rs671single nucleotide
polymorphism
CHROMOSOME 12Glu504Lys

01 / Read your data. Keep your privacy.

Asian Genomic Baseline Explorer

Open Regional SNP Parser
23andMe · AncestryDNA · MyHeritage

>_ Open Regional SNP Parserv1.0.0 / LOCAL

Your raw data never leaves your browser. Parsing occurs locally in memory and is discarded upon tab refresh.

No file at hand?
Where do I find my raw data file?

23andMe

  1. Sign in and open your profile menu. Choose Resources → Browse Raw Genotyping Data.
  2. Open Download, review the information, and submit your download request.
  3. Follow the link in the provider’s email, save the raw file, and select it here.
23andMe export instructions ↗

AncestryDNA

  1. Sign in, open your DNA results, and go to Settings for the relevant test.
  2. Under Download DNA Data, request your data and complete the identity confirmation.
  3. Use the confirmation email to download the ZIP file. You can select that ZIP directly here.
AncestryDNA export instructions ↗

MyHeritage exports are supported as CSV, TXT, or a ZIP containing one raw data file. Provider menus can vary by region. Use only data you have permission to examine.

02 / The biology behind the letters

One marker. A meaningful pathway.

Acetaldehyde metabolism &
cellular oxidative stress

Acetaldehydereactive aldehyde
ALDH2NAD+ → NADH
Acetatedownstream metabolite

[A] / ENZYME FUNCTION

A cellular clearance pathway

ALDH2 is a mitochondrial enzyme. It helps convert acetaldehyde, produced during alcohol metabolism, to acetate. It also participates in processing other reactive aldehydes. A genotype alone does not measure your current oxidative stress.

Read the mechanistic study ↗

[B] / SUBUNIT ASSEMBLY

Why a single letter matters

ALDH2 works as a four-subunit complex. At rs671, the A allele encodes a glutamate-to-lysine change (Glu504Lys; historically E487K). Altered subunits can reduce the activity of the mixed complex, so GA is associated with reduced function too.

Read the subunit research ↗

[C] / REGIONAL CONTEXT

Context, without assumptions

Allele frequencies differ across populations. East and Southeast Asia contain extensive genetic diversity; a regional label cannot predict your genotype. This parser reads an existing call and does not calculate ancestry, lifespan, or disease risk.

Explore population diversity ↗

03 / Public evidence. Inspectable sources.

Start with the source material.

GenomeAsia 100KRegional diversity and the 2019 pilot reference dataset.
1,739 genomes · 219 population groupsgnomAD / East AsianPopulation frequencies for rs671.
Select East Asian (EAS) in the ancestry table.ClinVar / rs671Variant submissions and cited studies.
Read the evidence and review status.
Parser documentation & the additional-locus index

Files are read in 256 KiB chunks using FileReader. Standard unencrypted ZIP files are decompressed incrementally in the browser and checked for integrity. Text formats with one genotype column or two allele columns are supported. No raw rows, file names, or additional genotypes are submitted.

rs671 must have an unambiguous GG, GA/AG, or AA call on chromosome 12. Missing calls, conflicting duplicates, and unsupported alleles are not interpreted. AG is displayed as GA. Reverse-strand calls are not automatically inferred. Consumer raw data can contain errors; the parser cannot verify laboratory accuracy.

The optional index checks 14 predefined metabolic or longevity research loci, including KCNQ1 and APOA5. Its count reflects readable genotype calls actually present in your export. Presence is not a risk finding or a longevity prediction. It does not constitute a validated panel. Individual variant records:

Population datasets are linked for context, not queried with your data. These resources do not endorse this tool. The GWAS Catalog’s 2023 publication reported 79% European-only studies in its catalog; that is a study statistic, not a measurement of commercial DNA platforms. GWAS Catalog source ↗

Data handling: local results use browser memory only. Clear or refresh to discard them. The optional email action sends only { email, genotype, rsid: "rs671" } to this site. The current placeholder endpoint discards requests and cannot deliver email. No biological data is retained remotely. Ordinary web infrastructure may record request metadata, but this app does not log request bodies. The page loads Tailwind from a CDN; the font and logo are embedded. No analytics, cookies, or browser storage are used.

ALDH2 / EDUCATIONAL SUMMARY

Marklar Systems / Open Regional SNP Parser / 01 of 02

ALDH2: acetaldehyde &
cellular oxidative stress

1. What this marker describes

ALDH2 encodes a mitochondrial aldehyde dehydrogenase. It helps convert acetaldehyde to acetate using NAD+ as a cofactor. Acetaldehyde is generated during ethanol metabolism; other reactive aldehydes can arise when lipids are oxidized. ALDH2 is one part of the cell’s aldehyde-processing machinery, not a general test of “detoxification.” [1, 2]

2. Why the A allele changes enzyme function

rs671 is a G-to-A substitution associated with Glu504Lys in the precursor protein, also called E487K in the mature enzyme. The G allele is associated with ALDH2*1; the A allele with ALDH2*2. ALDH2 assembles as a tetramer: four interacting protein subunits. The lysine substitution disrupts interactions important to coenzyme binding and catalysis. [1, 2]

In a person with GA, both types of subunit may be produced. Altered subunits can reduce the activity and stability of mixed complexes, a dominant-negative effect. One A copy therefore does not imply “half-normal” activity. AA is generally associated with a marked reduction in activity. Exact activity cannot be calculated from this raw call. [2, 3]

3. What this does—and does not—tell you

The A allele is associated with reduced acetaldehyde clearance. GG does not establish that alcohol is safe. No rs671 result measures your current oxidative stress, enzyme concentration, biological age, or personal probability of disease. Environment, exposures, other variants, and measurement error matter. [1–3]

Educational and research comparison only. Not a diagnosis, clinical test, or recommendation. If a finding might affect care, discuss appropriate clinical confirmation with a qualified professional. This document is generated locally; saving or printing creates a copy under your control.

Marklar Systems / Open Regional SNP Parser / 02 of 02

Evidence, context & limitations

4. Regional context is not a personal prediction

The A allele is more frequent in some East Asian populations, but frequencies vary within and across East and Southeast Asia. GenomeAsia illustrates this diversity with a pilot dataset spanning 219 population groups. gnomAD’s EAS label is an aggregate research grouping, not a proxy for every community or individual. [4, 5]

5. About this file scan

The parser reads the provider’s reported rs671 call on chromosome 12; it does not sequence DNA, impute missing variants, or infer ancestry. AG is normalized to GA. Uncalled genotypes, conflicting records, and unsupported allele orientations are not interpreted. Chip versions differ, and rs671 may be absent. A missing marker is not a GG result.

The additional index checks presence only. It supplies no polygenic score, disease prediction, or longevity estimate. Its variant list and links are in the page’s parser documentation. Consumer genotyping calls may require independent confirmation before any clinical use.

6. Scientific references & public datasets

  1. E487K-induced disorder in ALDH2 dynamics. Biophysical Journal (2020). Mechanistic analysis of the enzyme.
  2. Disruption of the coenzyme binding site and dimer interface. Journal of Biological Chemistry (2005). DOI: 10.1074/jbc.M502345200.
  3. Dominant effects on ALDH2 tetramer turnover. Journal of Clinical Investigation (1996). DOI: 10.1172/JCI119007.
  4. The GenomeAsia 100K Project. Nature (2019). DOI: 10.1038/s41586-019-1793-z.
  5. gnomAD v4 rs671 frequencies (GRCh38: 12-111803962-G-A). Consult the EAS ancestry row and coverage.
  6. ClinVar variation 18390. Inspect individual submissions, dates, evidence, and review status; an entry alone is not a diagnosis.

Prepared by Asian Genomic Baseline Explorer v1.0.0 · September 2026.
For educational and research comparison purposes only. Not intended to diagnose, treat, or provide clinical guidance. No biological data is retained on any remote server.