rs78655421
A SNP in the CFTR gene on chromosome 7. Its most notable genotype is A;G: Possible cystic fibrosis allele carrier, but of low penetrance
- Gene
- CFTR
- Location
- Chr 7117,530,975 (GRCh38)
- Highest magnitude
- 3.0Important
- Tested on
- 23andMe, AncestryDNA
Genotypes
As shown in 23andMe and AncestryDNA files.
- A;GMost notableBadPossible cystic fibrosis allele carrier, but of low penetrance
- G;GGoodcommon in clinvar
On SNPedia: (A;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Related
Conditions, medicines and genes
Other CFTR SNPs
- i4000292D;Dcystic fibrosisVery important
- rs74551128A;ACystic fibrosisVery important
- rs113993960-;-Cystic Fibrosis; homozygote for delta F-508 mutationVery important
- rs199826652-;-Cystic Fibrosis; homozygote for delta F-508 mutationVery important
- i4000309A;ACystic FibrosisVery important
- i4000294A;ACystic FibrosisVery important
- i4000296T;TCystic FibrosisVery important
- i4000297A;ACystic FibrosisVery important
Notes
From SNPedia
Show notes, about 120 words
This cystic fibrosis variant, c.350G>A, known as Arg117His or R117H and associated with a G>A mutation, is reported to have either mild or perhaps even no clinical consequences, apparently depending heavily on the length of the polypyrimidine tract in the splice acceptor site in intron 8 and possibly other variants as well. A good write-up on this can be found in OMIM 602421.0005. Other mutations possible at this position are G>C (Arg117Pro) and G>T (Arg117Leu), but their effect is not listed in ClinVar or CFTR2. rs78655421 is also named i5010839, i5006049 and i4000295 by 23andMe; while for them, i5010838 represents the G>C mutation and i5010837 the G>T. FTDNA & MyHeritage name: VG07S29628
A;G
See discussion at rs78655421.
Source and license
Adapted from rs78655421 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.