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BRCA2

From SNPedia

is agene
is mentioned by
Full namebreast cancer 2, early onset
EntrezGene675
PheGenI675
VariationViewer675
ClinVarBRCA2
dbSNP675
SADR675
HugeNav675
wikipediaBRCA2
googleBRCA2
gopubmedBRCA2
EVSBRCA2
HEFalMpBRCA2
23andMeBRCA2
UniProtP51587
EnsemblENSG00000139618
OMIM600185
EVSBRCA2
# SNPs1497
 Max MagnitudeChromosome positionSummary
Rs1049239632,384,750
Rs11571658632,340,630
Rs11571746232,370,971
Rs11571747232,371,035
Rs11571833232,398,489
Rs1157183632,399,302
Rs120074205632,326,255
Rs138734772032,333,072
Rs142899125032,362,582
Rs144848232,332,592
Rs145988146032,319,282
Rs169547032,355,250
Rs1799943032,316,435
Rs1799944232,337,326
Rs1799954232,340,455
Rs1801406032,337,751
Rs1801426232,398,747
Rs180670511032,341,109
Rs200265692032,339,435
Rs201523522032,319,180
Rs20611832,315,655
Rs276174811632,333,085
Rs276174813632,333,272
Rs276174814632,333,274
Rs276174815632,333,332
Rs276174819632,336,530
Rs276174822632,336,794
Rs276174823632,336,826
Rs276174824632,336,958
Rs276174825632,319,271
Rs276174826632,336,991
Rs276174833632,337,632
Rs276174838632,338,294
Rs276174839632,338,369
Rs276174842632,338,493
Rs276174843632,338,518
Rs276174844032,326,089
Rs276174846632,339,086
Rs276174847632,339,097
Rs276174848032,326,154
Rs276174852632,339,420
Rs276174853632,339,471
Rs276174854632,339,500
Rs276174857632,326,521
Rs276174859632,339,964
Rs276174860632,339,996
Rs276174861632,340,010
Rs276174862632,340,073
Rs276174864632,340,245
Rs276174865632,340,322
... further results


BRCA2 is a human tumor suppressor gene. Like most genes, variations in the BRCA2 gene can be either causal for a given disease, or associated with somewhat higher risk, or benign. In clinical terms, a "causal" variation is usually designated as "pathogenic".

However, "causal" (or "pathogenic") does not mean that there is a 100% certainty that a person with such a variant will develop the disease. The clinical synopsis in OMIM for cancers associated with causal BRCA2 mutations is [1]:

  • Mutation carriers have an increased risk of developing breast and/or ovarian cancer at an earlier age
  • Lifetime risk of breast cancer in mutation carriers is 60 to 85%
  • Lifetime risk of ovarian cancer in mutation carriers is 10 to 20%
  • Lifetime risk of breast cancer in male mutation carriers in 6%
  • Increased risk of bilateral breast cancer


There are hundreds of BRCA2 variants that are considered casual/pathogenic, but almost all are very rare (far less than 1% frequency each). [There are also hundreds of other BRCA2 variants that raise one's risk just a bit; these are usually found in 1 - 3% or higher frequencies.] Perhaps the "least rare" causal BRCA2 SNP is:


See also BRCA1 and BRCA2 for an extensive list of breast cancer related SNPs (including variations of all types from benign to causal).

Many other variations of varying consequence are known. 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]



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. [2]

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.