UniProtKB/Swiss-Prot O75444: Variant p.Lys297Arg

Transcription factor Maf
Gene: MAF
Chromosomal location: 16q23
Variant information

Variant position:  297
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 Lysine (K) to Arginine (R) at position 297 (K297R, p.Lys297Arg).
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 large size and basic.
The physico-chemical property of the reference and variant residues and the change implicated.

BLOSUM score:  2
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:  Cataract 21, multiple types (CTRCT21) [MIM:610202]: An opacification of the crystalline lens of the eye that frequently results in visual impairment or blindness. Opacities vary in morphology, are often confined to a portion of the lens, and may be static or progressive. In general, the more posteriorly located and dense an opacity, the greater the impact on visual function. CTRCT21 includes cerulean and pulverulent cataracts. Cerulean cataracts are characterized by peripheral bluish and white opacifications organized in concentric layers with occasional central lesions arranged radially. The opacities are observed in the superficial layers of the fetal nucleus as well as the adult nucleus of the lens. Involvement is usually bilateral. Visual acuity is only mildly reduced in childhood. In adulthood, the opacifications may progress, making lens extraction necessary. Histologically the lesions are described as fusiform cavities between lens fibers which contain a deeply staining granular material. Although the lesions may take on various colors, a dull blue is the most common appearance and is responsible for the designation cerulean cataract. Pulverulent cataracts are characterized by a dust-like, 'pulverised' appearance of the opacities which can be found in any part of the lens. In some cases cataract is associated with microcornea without any other systemic anomaly or dysmorphism. Microcornea is defined by a corneal diameter inferior to 10 mm in both meridians in an otherwise normal eye. 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 CTRCT21.
Any additional useful information about the variant.



Sequence information

Variant position:  297
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  373
The length of the canonical sequence.

Location on the sequence:   QLRGVSKEEVIRLKQKRRTL  K NRGYAQSCRFKRVQQRHVLE
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                         QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRFKRVQQRHVLE

Mouse                         QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRFKRVQQRHVLE

Rat                           QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRFKRVQQRHVLE

Bovine                        QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRFKRVQQRHVLE

Chicken                       QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRFKRVQQRHVLE

Xenopus tropicalis            QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRFKRVQQRHVLE

Zebrafish                     QLRGVSKEEVIRLKQKRRTLKNRGYAQSCRYKRVQQRHVLE

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 1 – 373 Transcription factor Maf
Domain 288 – 351 bZIP
Region 126 – 373 Represses ARE-mediated transcription
Region 288 – 313 Basic motif


Literature citations

A novel mutation in the DNA-binding domain of MAF at 16q23.1 associated with autosomal dominant 'cerulean cataract' in an Indian family.
Vanita V.; Singh D.; Robinson P.N.; Sperling K.; Singh J.R.;
Am. J. Med. Genet. A 140:558-566(2006)
Cited for: VARIANT CTRCT21 ARG-297;

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.