UniProtKB/Swiss-Prot P0DJI8: Variant p.Asp78Asn

Serum amyloid A-1 protein
Gene: SAA1
Chromosomal location: 11p15.1
Variant information

Variant position:  78
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 Aspartate (D) to Asparagine (N) at position 78 (D78N, p.Asp78Asn).
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 acidic (D) to medium size and polar (N)
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

Polymorphism:  At least 5 different SAA1 alleles have been described: SAA1.1 (SAA1alpha), SAA1.2 (SAA1beta), SAA1.3 (SAA1gamma), SAA1.4 (SAA1delta), SAA1.5 (also named SAA1beta but which differs from SAA1.2). We use here the revised nomenclature described in PubMed:10211414. The sequence shown is that of SAA1.1.
Additional information on the polymorphism described.

Variant description:  In allele SAA1.4.
Any additional useful information about the variant.



Sequence information

Variant position:  78
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  122
The length of the canonical sequence.

Location on the sequence:   GNYDAAKRGPGGVWAAEAIS  D ARENIQRFFGHGAEDSLADQ
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                         GNYDAAKRGPGGVWAAEAISDARENIQRFFGHGAEDSLADQ

Mouse                         GNYDAAQRGPGGVWAAEKISDGREAFQEFFGRGHEDTIADQ

Rabbit                        GNYDAAQRGPGGVWAAKVISDAREDLQRLMGHGAEDSMADQ

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 19 – 122 Serum amyloid A-1 protein
Chain 19 – 94 Amyloid protein A
Chain 20 – 122 Serum amyloid protein A(2-104)
Chain 20 – 121 Serum amyloid protein A(2-103)
Chain 20 – 120 Serum amyloid protein A(2-102)
Chain 21 – 122 Serum amyloid protein A(3-104)
Chain 22 – 119 Serum amyloid protein A(4-101)
Mutagenesis 65 – 65 R -> A. Reduces affinity for heparin; when associated with A-33 and A-37.
Mutagenesis 80 – 80 R -> A. Reduces affinity for heparin and nearly abolishes association with HDL; when associated with A-18 and A-89.
Mutagenesis 89 – 89 H -> A. Reduces affinity for heparin and nearly abolishes association with HDL; when associated with A-18 and A-80.
Helix 67 – 86


Literature citations

Heterogeneity of human serum amyloid A protein. Five different variants from one individual demonstrated by cDNA sequence analysis.
Steinkasserer A.; Weiss E.H.; Schwaeble W.; Linke R.P.;
Biochem. J. 268:187-193(1990)
Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 73-122; VARIANTS VAL-75 AND ASN-78;

Identification of two novel amyloid A protein subsets coexisting in an individual patient of AA-amyloidosis.
Baba S.; Takahashi T.; Kasama T.; Shirasawa H.;
Biochim. Biophys. Acta 1180:195-200(1992)
Cited for: PROTEIN SEQUENCE OF 19-94; MASS SPECTROMETRY; DISEASE; VARIANTS ALA-70; VAL-75 AND ASN-78; ALLELE SAA1.3;

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.