UniProtKB/Swiss-Prot O15118: Variant p.Val664Met

Niemann-Pick C1 protein
Gene: NPC1
Chromosomal location: 18q11-q12
Variant information

Variant position:  664
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  Disease [Disclaimer]
The variants are classified into three categories: Disease, Polymorphism and Unclassified.
  • Disease: Variants have been found in patients and disease-association is reported in literature. However, this classification is not a definitive assessment of variant pathogenicity.
  • Polymorphism: No disease-association has been reported.
  • Unclassified: Variants have been found in patients but disease-association remains unclear.

Residue change:  From Valine (V) to Methionine (M) at position 664 (V664M, p.Val664Met).
Indicates the amino acid change of the variant. The one-letter and three-letter codes for amino acids used in UniProtKB/Swiss-Prot are those adopted by the commission on Biochemical Nomenclature of the IUPAC-IUB.

Physico-chemical properties:  Similar physico-chemical property. Both residues are medium size and hydrophobic.
The physico-chemical property of the reference and variant residues and the change implicated.

BLOSUM score:  1
The score within a Blosum matrix for the corresponding wild-type to variant amino acid change. The log-odds score measures the logarithm for the ratio of the likelihood of two amino acids appearing by chance. The Blosum62 substitution matrix is used. This substitution matrix contains scores for all possible exchanges of one amino acid with another:
  • Lowest score: -4 (low probability of substitution).
  • Highest score: 11 (high probability of substitution).
More information can be found on the following page

Involvement in disease:  Niemann-Pick disease C1 (NPC1) [MIM:257220]: A lysosomal storage disorder that affects the viscera and the central nervous system. It is due to defective intracellular processing and transport of low-density lipoprotein derived cholesterol. It causes accumulation of cholesterol in lysosomes, with delayed induction of cholesterol homeostatic reactions. Niemann-Pick disease type C1 has a highly variable clinical phenotype. Clinical features include variable hepatosplenomegaly and severe progressive neurological dysfunction such as ataxia, dystonia and dementia. The age of onset can vary from infancy to late adulthood. An allelic variant of Niemann-Pick disease type C1 is found in people with Nova Scotia ancestry. Patients with the Nova Scotian clinical variant are less severely affected. Note=The disease is caused by mutations affecting the gene represented in this entry.
The name and a short description of the disease associated with the variant. For more information about the disease, the user can refer to OMIM, following the link provided after the disease acronym.

Variant description:  In NPC1.
Any additional useful information about the variant.



Sequence information

Variant position:  664
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  1278
The length of the canonical sequence.

Location on the sequence:   SCRRLLVDSKVSLGIAGILI  V LSSVACSLGVFSYIGLPLTL
The residue change on the sequence. Unless the variant is located at the beginning or at the end of the protein sequence, both residues upstream (20) and downstream (20) of the variant will be shown.

Residue conservation: 
The multiple alignment of the region surrounding the variant against various orthologous sequences.

Human                         SCRR----LLVDSKVSLGIAGILIVLSSVACSLGVFSYIGLPLTL

Mouse                         SCSR----LLVDSKISLGIAGILIVLSSVACSLGIFSYMGM

Pig                           SCSR----LLVDSKISLGIAGILIVLSSVACSLGIFSYIGV

Caenorhabditis elegans        VCENQLWSILVHSRICLGMLSVIINLLSSFCSWGIFSMFGI

Baker's yeast                 GKTR----LL------LGISGLLIVLASIVCAAGFLTLFGL

Sequence annotation in neighborhood:  
The regions or sites of interest surrounding the variant. In general the features listed are posttranslational modifications, binding sites, enzyme active sites, local secondary structure or other characteristics reported in the cited references. The "Sequence annotation in neighborhood" lines have a fixed format:
  • Type: the type of sequence feature.
  • Positions: endpoints of the sequence feature.
  • Description: contains additional information about the feature.

TypePositionsDescription
Chain 23 – 1278 Niemann-Pick C1 protein
Transmembrane 655 – 675 Helical;
Domain 620 – 785 SSD
Mutagenesis 660 – 660 G -> R. Loss of function.


Literature citations

Identification of 58 novel mutations in Niemann-Pick disease type C: correlation with biochemical phenotype and importance of PTC1-like domains in NPC1.
Park W.D.; O'Brien J.F.; Lundquist P.A.; Kraft D.L.; Vockley C.W.; Karnes P.S.; Patterson M.C.; Snow K.;
Hum. Mutat. 22:313-325(2003)
Cited for: VARIANTS NPC1 TYR-74; SER-166; SER-222; TYR-247; PHE-380; PRO-388; CYS-389; TRP-404; LEU-433; SER-509; SER-521; LEU-543; CYS-615; ARG-640; SER-660; MET-664; VAL-673; PHE-684; LEU-691; VAL-695; ASN-700; ILE-734; LYS-742; GLU-745; VAL-767; GLY-789; ASN-945; ARG-1016; GLN-1059; LEU-1087; ILE-1137; VAL-1140; LYS-1205 AND GLY-1249; VARIANTS ARG-215; SER-237; SER-434 AND GLN-1266;

Identification of 25 new mutations in 40 unrelated Spanish Niemann-Pick type C patients: genotype-phenotype correlations.
Fernandez-Valero E.M.; Ballart A.; Iturriaga C.; Lluch M.; Macias J.; Vanier M.T.; Pineda M.; Coll M.J.;
Clin. Genet. 68:245-254(2005)
Cited for: VARIANTS NPC1 MET-137; TYR-177; TRP-372; LEU-434; LEU-474; TYR-479; ARG-576; MET-664; PHE-727; LYS-754; PRO-775; LEU-865; THR-926; CYS-942; ASN-944; HIS-948; GLU-959; 961-ASN--PHE-966 DELINS SER; ALA-1007; VAL-1035; LYS-1036; THR-1061; ASN-1066; ILE-1156; SER-1156 AND LEU-1224; VARIANTS ARG-215; ILE-642; VAL-858 AND GLN-1266;

Disclaimer: Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. They are not in any way intended to be used as a substitute for professional medical advice, diagnostic, treatment or care.