UniProtKB/Swiss-Prot P07741: Variant p.Met136Thr

Adenine phosphoribosyltransferase
Gene: APRT
Chromosomal location: 16q24
Variant information

Variant position:  136
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 Methionine (M) to Threonine (T) at position 136 (M136T, p.Met136Thr).
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 hydrophobic (M) to medium size and polar (T)
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

Variant description:  In APRTD; Japanese type; allele APRT*J; most common mutation.
Any additional useful information about the variant.

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



Sequence information

Variant position:  136
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  180
The length of the canonical sequence.

Location on the sequence:   ALEPGQRVVVVDDLLATGGT  M NAACELLGRLQAEVLECVSL
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.

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 2 – 180 Adenine phosphoribosyltransferase
Modified residue 135 – 135 Phosphothreonine
Alternative sequence 134 – 180 GTMNAACELLGRLQAEVLECVSLVELTSLKGREKLAPVPFFSLLQYE -> V. In isoform 2.
Helix 134 – 145


Literature citations

Human adenine phosphoribosyltransferase. Identification of allelic mutations at the nucleotide level as a cause of complete deficiency of the enzyme.
Hidaka Y.; Palella T.D.; O'Toole T.E.; Tarle S.A.; Kelley W.N.;
J. Clin. Invest. 80:1409-1415(1987)
Cited for: VARIANT APRTD THR-136;

Human adenine phosphoribosyltransferase deficiency. Demonstration of a single mutant allele common to the Japanese.
Hidaka Y.; Tarle S.A.; Fujimori S.; Kamatani N.; Kelley W.N.;
J. Clin. Invest. 81:945-950(1988)
Cited for: VARIANTS APRTD THR-136 AND PHE-173 DEL;

Only three mutations account for almost all defective alleles causing adenine phosphoribosyltransferase deficiency in Japanese patients.
Kamatani N.; Hakoda M.; Otsuka S.; Yoshikawa H.; Kashiwazaki S.;
J. Clin. Invest. 90:130-135(1992)
Cited for: VARIANT APRTD THR-136;

A Japanese boy with adenine phosphoribosyltransferase (APRT) deficiency caused by compound heterozygosity including a novel missense mutation in APRT gene.
Nozue H.; Kamoda T.; Saitoh H.; Ichikawa K.; Taniguchi A.;
Acta Paediatr. 100:E285-E288(2011)
Cited for: VARIANTS APRTD PRO-33 AND THR-136;

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.