Home  |  Contact

UniProtKB/Swiss-Prot P22748: Variant p.Ala12Thr

Carbonic anhydrase 4
Gene: CA4
Chromosomal location: 17q23
Variant information

Variant position:  12
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 implicated in disease according to literature reports.
  • Polymorphism: Variants not reported to be implicated in disease.
  • Unclassified: Variants with uncertain implication in disease according to literature reports. Evidence against or in favor of a pathogenic role is limited and/or conflicting.

Residue change:  From Alanine (A) to Threonine (T) at position 12 (A12T, p.Ala12Thr).
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:  Change from small size and hydrophobic (A) to medium size and polar (T)
The physico-chemical property of the reference and variant residues and the change implicated.

BLOSUM score:  0
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:  Retinitis pigmentosa 17 (RP17) [MIM:600852]: A retinal dystrophy belonging to the group of pigmentary retinopathies. Retinitis pigmentosa is characterized by retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well. {ECO:0000269|PubMed:15563508, ECO:0000269|PubMed:17652713, ECO:0000269|PubMed:20450258}. Note=The disease is caused by mutations affecting the gene represented in this entry. Defective acid overload removal from retina and retinal epithelium, due to mutant CA4, is responsible for photoreceptor degeneration, indicating that impaired pH homeostasis is the most likely cause underlying the RP17 phenotype.
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 RP17.
Any additional useful information about the variant.

Other resources:  
Links to websites of interest for the variant.



Sequence information

Variant position:  12
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  312
The length of the canonical sequence.

Location on the sequence:   MRMLLALLALS  A ARPSASAESHWCYEVQAESS
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                         MRMLLALLALSAARPSASAESHWCYEVQAESS

Mouse                         MQLLLALLALAYVAPST-EDSGWCYEIQTKDP

Rat                           MQLLLALLALAYVAPST-EDSHWCYEIQAKEP

Bovine                        MRLLLALLVLAAAPPQARAASHWCYQIQVKPS

Rabbit                        MQLLFALLALGALRPLAGEELHWCYEIQA--S

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
Signal peptide 1 – 18


Literature citations

Screening for the carbonic anhydrase IV gene mutations in Chinese retinitis pigmentosa patients.
Tian Y.; Tang L.; Cui J.; Zhu X.;
Curr. Eye Res. 35:440-444(2010)
Cited for: VARIANT RP17 THR-12;

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.