rs28933979

A SNP in the TTR gene on chromosome 18. Its most notable genotype is A;G: TTR-related amyloidosis

Gene
TTR
Location
Chr 1831,592,974 (GRCh38)
Highest magnitude
5.5Very important
Tested on
Not on consumer chips

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. A;ABadTTR-related familial amyloid polyneuropathyVery important · 4.0
  2. A;GMost notableBadTTR-related amyloidosisVery important · 5.5
  3. C;GBadTTR-related amyloidosisVery important · 5.5
  4. G;GGoodcommon in clinvarTypical · 0.0

On SNPedia: (A;A), (A;G), (C;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Other TTR SNPs

All TTR SNPs

Notes

From SNPedia

Show notes, about 140 words

rs28933979, also known as V30M, V50M, Val30Met, Val50Met and 148G>A, is a mutation in the transthyretin TTR gene. The risk allele for this SNP, rs28933979(A), is considered causative for TTR-related familial amyloid polyneuropathy, with the majority of carriers developing the condition by the time they are 80, although the age of onset varies. This mutation is reported to be more common in Portugal as well as Sweden and Japan. A 2018 angiographic study of 18 V30M-confirmed patients reported that both retinal amyloid angiopathy (RAA) and choroidal amyloid angiopathy (CAA) were detected in 92% - 100% of eyes examined. 23andMe name: i3002758

A;A

The majority of people with this genotype develop the neurological condition known as TTR-related familial amyloid polyneuropathy by the time they are 80, although the age of onset varies.

Source and license

Adapted from rs28933979 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.

SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.