Certain variations in BRCA2 have been linked to breast cancer or other cancers. These include:
- rs1799944 (also known as N991D), risk allele G; associated with melanoma
- rs766173 (also known as N289H), risk allele G
- rs144848 (also known as N372H or Asn372His), risk allele G
- rs4987117 (also known as T1915M), risk allele T
- rs1799954 (also known as R2034C), risk allele T
- rs11571746 (also known as S2835P), risk allele C
- rs11571747 (also known as E2856A), risk allele C
- rs4987047 (also known as I2944F), risk allele T
- rs11571833 (also known as K3326stop), risk allele T
- rs1801426 (also known as I3412V), risk allele G
- rs28897756 (also known as P3039P or 9345G/A), risk allele A. Researchers suggest that a SNP in the BARD1 gene (also called BARD1 Cys557Ser) is an ancient variant that confers risk of single and multiple primary breast cancers, and this risk is amplified in carriers of the BRCA2 999del5 (codon 257, exon 9) mutation, which appears to be this SNP (rs28897756). [PMID 16768547]
- Among Ashkenazi Jews, the BRCA2 founder mutation for breast cancer is considered to be 6174delT. This variation is rs80359550. 23andMe reports it as i4000379 (DD or DI). The deletion is the risk allele. See the discussion in [OMIM].
The relative risk of breast cancer associated with PALB2 mutations was estimated to be 2.3 (two-fold). This is similar to the increase in risk seen with the CHEK2, ATM, and BRIP1 genes, reported by the same research group since 2002. PALB2 is the first low-risk gene protein product found that interacts with BRCA2 and all of the other low-risk genes, CHEK2, ATM, and BRIP1, are linked to BRCA1. Together, these genes are thought to account for around 2 percent of all breast cancer cases. 
This report from the NCI advises:
- The cost for genetic testing can range from several hundred to several thousand dollars.
- Because the results of genetic tests can affect a person's health insurance coverage, some individuals may not want to use their insurance to pay for testing.
- it can take several weeks or months for test results to become available.
See also BRCA1.