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In rare disease, data are more valuable when shared, and we encourage users of this resource to explore and contribute new variant data. Together these data may help improve the diagnostic journey for patients living with rare diseases.

X-linked hypophosphatemia (XLH)

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Lc-FAOD
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Long-Chain Fatty Acid Oxidation Disorders (LC-FAOD)

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Lc-FAOD
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Disclaimer: The information on this website is provided by Ultragenyx Pharmaceutical Inc. for educational purposes only. The data contained within are not intended to replace advice from a healthcare professional and should not be used for diagnosing or treating a health problem or disease. The databases are open-source and aim to provide high quality and timely data. While Ultragenyx attempts to confirm that the data submitted is accurate, Ultragenyx does not take responsibility for the quality or accuracy of the data contained within.​

Gene Disorder(s)​
ACADVL Very long chain Acyl-CoA dehydrogenase (VLCAD) deficiency​
CPT1A Carnitine palmitoyltransferase type I (CPT I) deficiency​​
CPT2 Carnitine palmitoyltransferase type II (CPT II) deficiency​
HADHA Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency​ or TFP deficiency ​​
HADHB Trifunctional protein deficiency (TFP) deficiency​​​
SLC25A20​ Carnitine-acylcarnitine translocase (CACT) deficiency​



Scientific Variant

cDNA changes in the form of ACMG standard format.

Plain Language Variant

A Variant is a change or variation in the DNA sequence of a gene and is written following a standard format or nomenclature. Variants on this website are based on the coding (c.) DNA sequence position and follow the current variant nomenclature guidelines established by the Human Genome Variation Society (HGVS). For example, c.1328G>C represents a coding DNA change at position 1328 from guanine (G) to (>) cytosine (C).


Scientific Variant ID

The ID number assigned by the database to a specific variant.

Plain Language Variant ID

The Variant ID is an identification (ID) number assigned by the database to a unique variant.


Scientific Genomic Coordinate (GRCh38)

Numbered position in the coding sequence of the reference genome where the variant starts.

Plain Language Genomic Coordinate (GRCh38)

Genomic Coordinate consists of chromosome name and integers that together define a location (position or series of nucleotides) within a reference genome. The information specified typically includes chromosome name, start position, end position, and chromosome strand.


Scientific Variant Start Position

Numbered position in the coding sequence of the gene where the variant starts.

Plain Language Variant Start Position

The Variant Start Position is the first numbered position in the DNA coding sequence of the gene where the variant starts.


Scientific Location

Region of the gene or surrounding sequence where the variant starts.

Plain Language Location

The Location is the region of the gene or surrounding sequence where the variant starts.


Scientific Amino Acid Change

Amino acid change associated with the cDNA change in standard ACMG format.

Plain Language Amino Acid Change

Gene variants may change the amino acid sequence of a protein. The predicted change that a variant may cause to the amino acid sequence of the protein is written following a standard format. For example, Arg stands for the amino acid Arginine. The Amino Acid Change is shown as the expected protein (p.) amino acid (Arg) at a numerical position (443) followed by the amino acid encoded by the change (Pro). For example, p.Arg443Pro represents a change from Arginine at position 443 to Proline.


Scientific ACMG Call

Interpretation of the variant in ACMG format (e.g. pathogenic, likely pathogenic, variant of uncertain significance/VUS) as reported by the clinical testing laboratory.

Plain Language ACMG Call

Gene variants are classified according to the likelihood of causing disease and follow guidelines from the American College of Medical Genetics and Genomics (ACMG). In this database, variants with an ACMG Call are provided by a CLIA-certified laboratory. This database focuses on variants in the following categories: variants with significant evidence to be associated with disease (pathogenic, P), variants with evidence likely to be disease causing (likely pathogenic, LP), or variants that are rare and may have some disease association evidence but still lack enough evidence to be associated with disease (variants of uncertain significance, VUS).


Scientific Last Revised Date

Date the variant was submitted or date of the last update to the variant classification provided to the website.

Plain Language Last Revised Date

The Last Revised Date is either the date the variant was first submitted or the date of last update to the variant classification provided to the website.


Scientific Predicted ACMG Call

Interpretation of the variant as reported in the literature or by use of computational programs.

Plain Language Predicted ACMG Call

A Predicted ACMG Call is provided for variants as reported in published medical literature or by use of computational methods but have not yet, as of a last revised date, been reported and/or reviewed by a CLIA certified laboratory and submitted to this database with associated evidence.


Scientific Predicted ACMG Call

Effect type can be: Deletion, Untranslated region, Frameshift, Missense, Nonsense, Synonymous/Silent, Splice donor, Splice acceptor, Duplication, Intronic, Insertion, and Deletion/Insertion.

Plain Language Predicted ACMG Call

The change or ‘effect’ that a gene variant has on a protein is reported according to the Effect Type. This includes: Deletion: parts of the DNA are missing; Untranslated region: a change in the part of the gene that controls “gene expression” (how the RNA is made from DNA or how the RNA is processed) but does not occur in the part of the DNA that describes which amino acids to place in the protein; Frameshift: amino acids are represented by three DNA/RNA sequences that represent 64 codons. The protein sequence is described by the RNA message and is “read” three nucleotide “codons” at a time whereby one of about 64 possible codons represents 20 amino acids. There are synonym codons for amino acids: this results in more codons than the number of amino acids. For example, there are 4 codons that describe the amino acid Proline (Pro). If there is an insertion or deletion in the DNA, this “frame” of three nucleotides is disrupted or shifted (frameshift) and can result in the protein terminating early and/or can result in different/incorrect amino acids being encoded; Missense: a change in DNA that changes which amino acid is used in the protein at one position; Nonsense: an early signal to stop making the protein due to a change in the DNA which changes an amino acid codon to a stop codon; Synonymous/Silent: a change in the DNA which results in a new codon but the codon still calls for the same amino acid to be placed in the same position. These changes, even though they do not affect the amino acid sequence sometimes can in fact affect splicing (how an RNA is assembled to create the final message that is translated from RNA to protein). Depending on where this change occurs, a silent change with respect to which amino acid is coded may be shown to affect how RNA is made; Splice donor or Splice acceptor: a change in the DNA that affects how RNA is trimmed to make the final protein coding message; Duplication: a part of the DNA is repeated; Intronic: a change in the DNA that does not code for amino acids but may affect how RNA is made and therefore how protein is made; Insertion: new DNA sequence added; and Deletion/Insertion: parts of the DNA is missing and a new sequence is added.


Scientific Variant Type

Gene variants are described according to the Variant Type, which include: CNV, copy number variant which here describes a change 100 DNA nucleotides or larger; SNV, single DNA nucleotide variant; small insertion; splicing, affects how RNA is made; small deletion; and small duplication.

Plain Language Variant Type

Gene variants are described according to the Variant Type, which include: CNV, copy number variant which here describes a change 100 DNA nucleotides or larger; SNV, single DNA nucleotide variant; small insertion; splicing, affects how RNA is made; small deletion; and small duplication.


Scientific PMID

The PMID references abstracts for a published article associated with the variant.

Plain Language PMID

The PubMed ID or PMID is the unique identifier number used in PubMed which is a free search engine of references on life sciences and biomedical topics and is maintained by the National Center for Biotechnology Information (NCBI). The PMID references abstracts for a published article associated with the variant.


Scientific Article Count

The number of PubMed articles associated with the variant.

Plain Language Article Count

The Article Count is the number of PubMed articles associated with the variant.


Scientific Times Observed

The number of times a variant has been observed in patients. To protect privacy, individual patient counts are not provided.

Plain Language Times Observed

The number of times a variant has been observed in patients is referenced here as Times Observed. To protect privacy, individual patient counts are not provided.


ScientificClinical and Biochemical Phenotype

The clinical and biochemical signs and symptoms (phenotypes) reported for all patients with the variant. To protect privacy, individual patient information is not provided.

Plain Language Clinical and Biochemical Phenotype

The clinical and biochemical signs and symptoms reported for all patients with the variant are referred to as Clinical and Biochemical Phenotype. To protect privacy, individual patient information is not provided.

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