Sequencings

Markers / SCN9A

rs3750904

Neanderthal: pain sensitivity, D1908G

GeneSCN9A
Positionchr2:167,055,393
VersionsT / C
Evidencestrong

What this position does

Neanderthals carried three changes in the sodium channel that carries pain signals. People who inherited them report more pain, and in laboratory testing have a lower threshold for mechanical pain. The variants are essentially absent in Europeans and common in Latin American populations.

What each result means

If you carryWhat it means
No copies of the effect version
TT
Not inherited
Neither copy carries this Neanderthal change.
One copy
CT
Inherited from one parent
One copy, associated with somewhat greater pain sensitivity. The effects of the three variants add up.
Two copies
CC
Inherited from both parents
Two copies, associated with the greatest effect on pain threshold of the three.

How common each version is

Ancestry groupC (the effect version)
African0.3%
American26.2%
East Asian13.6%
European0.0%
South Asian0.5%

1000 Genomes Project phase 3, via Ensembl, retrieved 2026-09-23. These groupings are coarse and flatten a great deal of internal diversity, particularly within Africa. A variant being common somewhere tells you where a piece of your ancestry probably comes from, and nothing else.

How many people carry each result

Ancestry groupTTCTCC
African657 / 6614 / 6610 / 661
European503 / 5030 / 5030 / 503
East Asian381 / 504109 / 50414 / 504
South Asian484 / 4895 / 4890 / 489
American202 / 347108 / 34737 / 347

Counts of people, not modelled frequencies: every one of the 2,504 individuals sequenced by the 1000 Genomes Project phase 3, tallied by the genotype they carry. Deriving these from allele frequencies instead would assume random mating inside each group and undercount the homozygotes.

How to find out which you have

If you have taken a test with 23andMe, AncestryDNA, MyHeritage, Family Tree DNA, TellMeGen or Living DNA, this position is very likely already in the raw data file they gave you. You do not need another test.

One thing to watch if you look it up by hand: testing companies report some positions from one DNA strand and some from the other, and the file does not say which. Read the letters as they appear and you will get the opposite of the truth for some positions. Sequencings resolves that automatically.

Source

Zeberg et al., A Neanderthal sodium channel increases pain sensitivity in present-day humans, Current Biology (2020); Desai et al., Neanderthal introgression in SCN9A impacts mechanical pain sensitivity, Communications Biology (2023)

Coordinates and allele pair verified against Ensembl GRCh37. Direction of effect verified against VEP protein consequences or 1000 Genomes population frequency. Category: Archaic DNA.

Related

All markers in SCN9A

Where this fits

Common questions

What is rs3750904?

rs3750904 is a position in the SCN9A gene on chromosome 2. Neanderthals carried three changes in the sodium channel that carries pain signals. People who inherited them report more pain, and in laboratory testing have a lower threshold for mechanical pain. The variants are essentially absent in Europeans and common in Latin American populations.

What does it mean if I have CC at rs3750904?

Inherited from both parents. Two copies, associated with the greatest effect on pain threshold of the three.

What does it mean if I have TT at rs3750904?

Not inherited. Neither copy carries this Neanderthal change.

How do I find out my rs3750904 genotype?

If you have taken a home DNA test, this position is very likely in the raw data file you were given. Sequencings reads that file in your browser without uploading it, and resolves which DNA strand each position was reported from, which is the step most manual lookups get wrong.

This is reference information, not medical advice, and not a diagnosis. See the medical disclaimer. Category: Archaic DNA.