UniProtKB/Swiss-Prot P22309: Variant p.Gln331Arg

UDP-glucuronosyltransferase 1-1
Gene: UGT1A1
Chromosomal location: 2q37
Variant information

Variant position:  331
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 Glutamine (Q) to Arginine (R) at position 331 (Q331R, p.Gln331Arg).
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 medium size and polar (Q) to large size and basic (R)
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:  Crigler-Najjar syndrome 2 (CN2) [MIM:606785]: Patients have less severe hyperbilirubinemia and usually survive into adulthood without neurologic damage. Phenobarbital, which induces the partially deficient glucuronyl transferase, can diminish the jaundice. CN2 inheritance is autosomal dominant. 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 CN2; has no residual bilirubin glucuronidation activity.
Any additional useful information about the variant.



Sequence information

Variant position:  331
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  533
The length of the canonical sequence.

Location on the sequence:   VSEIPEKKAMAIADALGKIP  Q TVLWRYTGTRPSNLANNTIL
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                         VSEIPEKKAMAIADALGKIPQTVLWRYTGTRPSNLANNTIL

Mouse                         VSEIPEKKAMEIAEALGRIPQTVLWRYTGTRPSNLAKNTIL

Rat                           VSEIPEKKAMEIAEALGRIPQTVLWRYTGTRPSNLAKNTIL

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 26 – 533 UDP-glucuronosyltransferase 1-1
Glycosylation 347 – 347 N-linked (GlcNAc...)


Literature citations

Crigler-Najjar syndrome in The Netherlands: identification of four novel UGT1A1 alleles, genotype-phenotype correlation, and functional analysis of 10 missense mutants.
Sneitz N.; Bakker C.T.; de Knegt R.J.; Halley D.J.; Finel M.; Bosma P.J.;
Hum. Mutat. 31:52-59(2010)
Cited for: FUNCTION; SUBSTRATE SPECIFICITY; VARIANT CN1 THR-402; VARIANTS CN2 ARG-15; ARG-71; PHE-191; TRP-209; TRP-336; HIS-387; PRO-443 AND ASP-486; CHARACTERIZATION OF VARIANT CN1 THR-402; CHARACTERIZATION OF VARIANTS CN2 ARG-71; GLN-175; PHE-191; TRP-209; ARG-331; TRP-336; HIS-387; VAL-395 AND PRO-443;

Identification of an A-to-G missense mutation in exon 2 of the UGT1 gene complex that causes Crigler-Najjar syndrome type 2.
Moghrabi N.; Clarke D.J.; Boxer M.; Burchell B.;
Genomics 18:171-173(1993)
Cited for: VARIANT CN2 ARG-331;

Genetic lesions of bilirubin uridine-diphosphoglucuronate glucuronosyltransferase (UGT1A1) causing Crigler-Najjar and Gilbert syndromes: correlation of genotype to phenotype.
Kadakol A.; Ghosh S.S.; Sappal B.S.; Sharma G.; Chowdhury J.R.; Chowdhury N.R.;
Hum. Mutat. 16:297-306(2000)
Cited for: VARIANTS CN1 ASP-39; PHE-170 DEL; ARG-177; ARG-276; VAL-291; GLU-308; TRP-336; ARG-357; THR-368; PHE-375; ARG-381; SER-387; PRO-401 AND GLU-428; VARIANTS CN2 ARG-15; GLN-175; TRP-209; GLY-225 AND ARG-331; VARIANTS GILBS ARG-71; GLN-229; THR-294; GLY-367 AND ASP-486;

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.