• Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit




Associated disorders

The ABRAXAS1 gene, formerly known as FAM175A, currently has no well-established disease association; however, there is preliminary evidence supporting a correlation with autosomal dominant susceptibility to breast cancer (PMID: 22357538).

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Invitae tests that include this gene:

The ABRAXAS1 gene, formerly known as FAM175A, encodes the abraxas protein, which binds RAP80 and BRCA1 to target sites of DNA damage that require repair.

ABRAXAS1 heterozygote
OMIM: 610089

Clinical condition
There is preliminary evidence suggesting variants in ABRAXAS1 may be associated with a predisposition to breast cancer (PMID: 22357538). This is based on a study that identified a ABRAXAS1 variant, c.1082G>A, segregating with breast cancer (PMID: 22357538). These preliminary data, however, are currently insufficient to make a clear determination regarding this association. The risk for other cancers may be elevated in individuals with ABRAXAS1 variants; however, this evidence is also limited and emerging.

ABRAXAS1 is considered a preliminary evidence gene on the Invitae Breast Cancer Panel and the Invitae Breast and Gyn Cancers Panel. preliminary evidence genes are selected from an extensive review of the literature and expert recommendations, but the association between the gene and the specific condition has not been completely established. This uncertainty may be resolved as new information becomes available, and therefore clinicians may continue to order these preliminary evidence genes.

Gene information
ABRAXAS1 is a tumor suppressor gene playing a role in DNA repair and maintaining genome stability. It is also likely to be part of the BRCA1 signaling that contributes to tumor suppression (PMID: 25066119).

Variants in ABRAXAS1 have autosomal dominant inheritance. This means that an individual with a variant has a 50% chance of passing that variant on to their offspring.

Because the evidence regarding ABRAXAS1 and breast cancer risk is limited and preliminary, there are no guidelines or recommendations to suggest alteration to medical management based solely on the presence of a ABRAXAS1 variant. However, an individual’s cancer risk and medical management are not determined by genetic test results alone. Overall cancer risk assessment incorporates additional factors, including personal medical history, family history, and any available genetic information that may result in a personalized plan for cancer prevention and surveillance.

It is advantageous to know if a variant is present even though the the data regarding ABRAXAS1 are currently limited. At-risk relatives can be identified, allowing pursuit of a diagnostic evaluation. In addition, the available information regarding hereditary cancer susceptibility genes is constantly evolving and clinically relevant ABRAXAS1 data are likely to become available in the future. Awareness of this variant encourages patients and their providers to inform at-risk family members, to diligently follow condition-specific screening protocols, and to be vigilant in maintaining close and regular contact with their local genetics clinic in anticipation of new information.

Review date: September 2015

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons and 10 to 20 base pairs of adjacent intronic sequence on either side of the coding exons in the transcript listed below. In addition, the analysis covers the select non-coding variants specifically defined in the table below. Any variants that fall outside these regions are not analyzed. Any limitations in the analysis of these genes will be listed on the report. Contact client services with any questions.

Based on validation study results, this assay achieves >99% analytical sensitivity and specificity for single nucleotide variants, insertions and deletions <15bp in length, and exon-level deletions and duplications. Invitae's methods also detect insertions and deletions larger than 15bp but smaller than a full exon but sensitivity for these may be marginally reduced. Invitae’s deletion/duplication analysis determines copy number at a single exon resolution at virtually all targeted exons. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. Certain types of variants, such as structural rearrangements (e.g. inversions, gene conversion events, translocations, etc.) or variants embedded in sequence with complex architecture (e.g. short tandem repeats or segmental duplications), may not be detected. Additionally, it may not be possible to fully resolve certain details about variants, such as mosaicism, phasing, or mapping ambiguity. Unless explicitly guaranteed, sequence changes in the promoter, non-coding exons, and other non-coding regions are not covered by this assay. Please consult the test definition on our website for details regarding regions or types of variants that are covered or excluded for this test. This report reflects the analysis of an extracted genomic DNA sample. In very rare cases, (circulating hematolymphoid neoplasm, bone marrow transplant, recent blood transfusion) the analyzed DNA may not represent the patient's constitutional genome.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
ABRAXAS1 NM_139076.2