UniProtKB/Swiss-Prot P05067: Variant p.Asp678Asn

Amyloid beta A4 protein
Gene: APP
Chromosomal location: 21q21.2
Variant information

Variant position:  678
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 Aspartate (D) to Asparagine (N) at position 678 (D678N, p.Asp678Asn).
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

Involvement in disease:  Alzheimer disease 1 (AD1) [MIM:104300]: A familial early-onset form of Alzheimer disease. It can be associated with cerebral amyloid angiopathy. Alzheimer disease is a neurodegenerative disorder characterized by progressive dementia, loss of cognitive abilities, and deposition of fibrillar amyloid proteins as intraneuronal neurofibrillary tangles, extracellular amyloid plaques and vascular amyloid deposits. The major constituent of these plaques is the neurotoxic amyloid-beta-APP 40-42 peptide (s), derived proteolytically from the transmembrane precursor protein APP by sequential secretase processing. The cytotoxic C-terminal fragments (CTFs) and the caspase-cleaved products such as C31 derived from APP, are also implicated in neuronal death. {ECO:0000269|PubMed:10097173, ECO:0000269|PubMed:10631141, ECO:0000269|PubMed:10665499, ECO:0000269|PubMed:10867787, ECO:0000269|PubMed:11063718, ECO:0000269|PubMed:11528419, ECO:0000269|PubMed:12034808, ECO:0000269|PubMed:1302033, ECO:0000269|PubMed:1303239, ECO:0000269|PubMed:1303275, ECO:0000269|PubMed:1415269, ECO:0000269|PubMed:15201367, ECO:0000269|PubMed:15365148, ECO:0000269|PubMed:15668448, ECO:0000269|PubMed:1671712, ECO:0000269|PubMed:1678058, ECO:0000269|PubMed:1908231, ECO:0000269|PubMed:1925564, ECO:0000269|PubMed:1944558, ECO:0000269|PubMed:8267572, ECO:0000269|PubMed:8290042, ECO:0000269|PubMed:8476439, ECO:0000269|PubMed:8577393, ECO:0000269|PubMed:9328472, ECO:0000269|PubMed:9754958}. 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 AD1.
Any additional useful information about the variant.



Sequence information

Variant position:  678
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  770
The length of the canonical sequence.

Location on the sequence:   LTNIKTEEISEVKMDAEFRH  D SGYEVHHQKLVFFAEDVGSN
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                         LTNIK-------------TEEISEVKMDAEFRHD----------------SGYEVHHQKLVFFAEDVGSN

Chimpanzee                    LTNIK-------------TEEISEVKMDAEFRHD-------

Mouse                         LTNIK-------------TEEISEVKMDAEFGHD-------

Rat                           LTNIK-------------TEEISEVKMDAEFGHD-------

Pig                           LTNIK-------------TEEISEVKMDAEFRHD-------

Caenorhabditis elegans        STSSE--------SDEDEDKNIKELRVDIEPIIDEP-----

Drosophila                    VSSTKVQTVLPTVDDDAVQRAVEDVAAAVAHQEAEPQVQHF

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 18 – 770 Amyloid beta A4 protein
Chain 18 – 687 Soluble APP-alpha
Chain 672 – 770 C99
Chain 672 – 713 Beta-amyloid protein 42
Chain 672 – 711 Beta-amyloid protein 40
Topological domain 18 – 699 Extracellular
Metal binding 677 – 677 Copper or zinc 2
Metal binding 681 – 681 Copper or zinc 2
Metal binding 684 – 684 Copper or zinc 2
Metal binding 685 – 685 Copper or zinc 2
Glycosylation 659 – 659 O-linked (GalNAc...)
Glycosylation 663 – 663 O-linked (GalNAc...)
Glycosylation 667 – 667 O-linked (GalNAc...)
Glycosylation 679 – 679 O-linked (GalNAc...)
Glycosylation 697 – 697 O-linked (GalNAc...)
Alternative sequence 306 – 770 Missing. In isoform APP305.
Mutagenesis 676 – 676 R -> G. 60-70% zinc-induced beta-APP (28) peptide aggregation.
Mutagenesis 681 – 681 Y -> F. 60-70% zinc-induced beta-APP (28) peptide aggregation.
Mutagenesis 684 – 684 H -> R. Only 23% zinc-induced beta-APP (28) peptide aggregation.


Literature citations

Novel amyloid precursor protein gene missense mutation (D678N) in probable familial Alzheimer's disease.
Wakutani Y.; Watanabe K.; Adachi Y.; Wada-Isoe K.; Urakami K.; Ninomiya H.; Saido T.C.; Hashimoto T.; Iwatsubo T.; Nakashima K.;
J. Neurol. Neurosurg. Psych. 75:1039-1042(2004)
Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 672-723; VARIANT AD1 ASN-678;

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.