Home  |  Contact
Due to scheduled maintenance work, this service will not be available from Tuesday August 23rd 06:00 pm until Wednesday August 24th 08:00 am CEST. Apologies for the inconvenience.

UniProtKB/Swiss-Prot P06865: Variant p.Asn399Asp

Beta-hexosaminidase subunit alpha
Gene: HEXA
Variant information

Variant position:  399
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  LB/B
The variants are classified into three categories: LP/P, LB/B and US.
  • LP/P: likely pathogenic or pathogenic.
  • LB/B: likely benign or benign.
  • US: uncertain significance

Residue change:  From Asparagine (N) to Aspartate (D) at position 399 (N399D, p.Asn399Asp).
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 (N) to medium size and acidic (D)
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

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



Sequence information

Variant position:  399
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  529
The length of the canonical sequence.

Location on the sequence:   NKVKIQPDTIIQVWREDIPV  N YMKELELVTKAGFRALLSAP
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 89 – 529 Beta-hexosaminidase subunit alpha
Alternative sequence 361 – 529 Missing. In isoform 2.


Literature citations

Six novel deleterious and three neutral mutations in the gene encoding the alpha-subunit of hexosaminidase A in non-Jewish individuals.
Mules E.H.; Hayflick S.; Miller C.S.; Reynolds L.W.; Thomas G.H.;
Am. J. Hum. Genet. 50:834-841(1992)
Cited for: VARIANT GM2G1 GLY-320 DEL; VARIANTS ASP-399 AND VAL-436;

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.