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rs121918393

From SNPedia

Orientationplus
Stabilizedplus
Geno Mag Summary
(A;A) 6 Two copies of ApoE3 Christchurch variant (apparently)
(A;C) 5 Carrier of one ApoE3 Christchurch variant (most likely)
(C;C) 0 common in clinvar
ReferenceGRCh38 38.1/141
Chromosome19
Position44908756
GeneAPOE
is asnp
is mentioned by
dbSNPrs121918393
dbSNP (classic)rs121918393
ClinGenrs121918393
ebirs121918393
HLIrs121918393
Exacrs121918393
Gnomadrs121918393
Varsomers121918393
LitVarrs121918393
Maprs121918393
PheGenIrs121918393
Biobankrs121918393
1000 genomesrs121918393
hgdprs121918393
ensemblrs121918393
geneviewrs121918393
scholarrs121918393
googlers121918393
pharmgkbrs121918393
gwascentralrs121918393
openSNPrs121918393
23andMers121918393
23andMe allrs121918393
SNPshotrs121918393
SNPdbers121918393
MSV3drs121918393
GWAS Ctlgrs121918393
Max Magnitude6

aka c.460C>A (p.Arg154Ser or R154S); but also known based on older literature as p.Arg136Ser or R136S

This SNP is a variant form of an ApoE-ε3 allele, called the Christchurch mutation or ApoE-ε3ch. The variant has been strongly associated with type III hyperlipoproteinemia.[1]

There is evidence to suggest that ApoE-ε3ch may be associated with strong resistance to developing Alzheimer's disease. A 2019 study [2] reported that that a carrier of a pathogenic PSEN1 mutation, known to cause early-onset Alzheimer's disease, who was also a homozygous ApoE3ch carrier, did not show cognitive symptoms before her seventies, almost three decades after expected onset. Autosomal dominant forms of Alzheimer's disease and sporadic Alzheimer's disease show largely similar pathogenesis. Likewise, common APOE alleles(ApoE-ε2, ApoE-ε3, and ApoE-ε4) have similar effects in autosomal dominant Alzheimer's disease ([3], ApoE-ε4 carriers have earlier onset, ApoE-ε2 alleles have later onset). Together, this these findings suggest that being a homozygous ApoE-ε3ch carrier will potentially also convey protection against sporadic Alzheimer's disease. Furthermore, assuming that ApoE-ε3ch follows an allele-dose risk pattern similar to what has been observed for common APOE alleles [4], heterozygous ApoE-ε3ch carriage may also be convey protection against sporadic Alzheimer's disease.

OMIM107741
Desc
Variant0003
Relatedalso
ClinVar
Risk Rs121918393(A;A) rs121918393(T;T)
Alt Rs121918393(A;A) rs121918393(T;T)
Reference Rs121918393(C;C)
Significance Pathogenic
Disease Familial type 3 hyperlipoproteinemia
Variation info
Gene APOE
CLNDBN Familial type 3 hyperlipoproteinemia
Reversed 0
HGVS NC_000019.9:g.45412013C>A
CLNSRC OMIM Allelic Variant UniProtKB (protein)
CLNACC RCV000019430.25,