Skip to content

gnomAD

gnomAD is the quickest way to answer the question that often changes an interpretation: how rare is this variant, and how constrained is this gene in population data? It matters because frequency and constraint are among the fastest filters for separating plausible signals from common background variation.

In BioMCP, gene constraint comes from the gnomAD source path directly, and variant population data now does too. Variant population requests are pinned to the gnomad_r4 dataset and require a trustworthy GRCh38 coordinate. This replaces population fields previously copied from MyVariant.info payloads.

What BioMCP exposes

Command What BioMCP gets from this source Integration note
get gene <symbol> constraint Gene-level constraint metrics such as LOEUF-style context Direct gnomAD-backed gene section
get variant <id> population Compact exome/genome frequencies, highest observed population-row frequency with AC/AN, grpmax FAF95, and quality flags Direct gnomad_r4 GraphQL query for the resolved GRCh38 coordinate
get variant <id> population-details Full exome/genome ancestry tables Uses the same direct gnomad_r4 result
search variant -g <gene> --max-frequency <value> Rarity-filtered variant search rows Search filter uses population-frequency context aligned with gnomAD fields

Example commands

biomcp get gene BRAF constraint

Returns a constraint section with gnomAD provenance and LOEUF-style metrics.

biomcp get variant rs113488022 population

Returns compact direct gnomAD v4 exome and genome population results. For the highest observed population-row frequency, allele count (AC) is shown over allele number (AN). AN is the AF denominator: the number of alleles with a defined genotype call at that site, not a count of samples or people. JSON keeps raw numeric frequencies, counts, FAF95, ancestry rows, and source flag names.

biomcp get variant "chr7:g.140453136A>T" population
biomcp get variant "chr7:g.140453136A>T" population-details

The first command returns compact frequencies; the second returns full ancestry tables. A GRCh37-only or unknown-build result explains the requirement and does not query gnomAD.

biomcp search variant -g BRCA1 --max-frequency 0.01 --limit 5

Returns variant rows constrained by a rarity filter.

API access

No BioMCP API key required.

Official source

gnomAD is the official Broad Institute population-resource homepage behind these frequency and constraint views.