UniProtKB/Swiss-Prot Q96PL5: Variant p.Gly57Arg

Erythroid membrane-associated protein
Gene: ERMAP
Chromosomal location: 1p34
Variant information

Variant position:  57
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  Polymorphism
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 Glycine (G) to Arginine (R) at position 57 (G57R, p.Gly57Arg).
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 glycine (G) to large size and basic (R)
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

Polymorphism:  ERMAP is responsible for the Scianna/Radin blood group system which comprises seven different antigens. The Sc1 and Sc2 antigens are resulting from a single variation in position 57; Arg-57 corresponds to the Sc2 antigen and Gly-57 to the Sc1 antigen. The Sc2 antigen is rare with an occurrence of less than 1% in the population while Sc1 is more frequent. Sc3 is not expressed by individuals homozygous for a null allele encoding a truncated protein lacking its extracellular part (Sc-3). The Sc4 antigen corresponding to the previously defined Radin blood group antigen (Rd) is due to a single variation in position 60; Ala-60 corresponds to Sc4/Rd(+), the antigenic form of the protein. Sc4 is found in less than 1% of the population. Sc5/STAR, Sc6/SCER and Sc7/SCAN antigens are due to single variations in positions 47, 81 and 35 respectively. Alloantibodies to the low frequency Sc2 and Sc4 antigens are the cause of hemolytic disease in the newborn.
Additional information on the polymorphism described.

Variant description:  In Sc2 antigen.
Any additional useful information about the variant.

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



Sequence information

Variant position:  57
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  475
The length of the canonical sequence.

Location on the sequence:   FHVALLGGTAELLCPLSLWP  G TVPKEVRWLRSPFPQRSQAV
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                         FHVALLGGTAELLCPLSLWPGTVPKEVRWLRSPFPQRSQAV

Mouse                         VYIAPLRDTANLPCPLFLWPNMVLSEMRWYRPGHLPRTQAV

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 30 – 475 Erythroid membrane-associated protein
Topological domain 30 – 155 Extracellular
Domain 30 – 140 Ig-like V-type
Disulfide bond 50 – 126


Literature citations

Scianna antigens including Rd are expressed by ERMAP.
Wagner F.F.; Poole J.; Flegel W.A.;
Blood 101:752-757(2003)
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ALLELE SC-3); VARIANTS BLOOD GROUP SC2 ARG-57 AND SC4 ALA-60; VARIANT TYR-26;

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.