INTRODUCTION
Both BRCA genes are tumor suppressor genes that produce proteins that are used by the cell
in an enzymatic pathway that makes very precise, perfectly matched repairs to DNA molecules.
Harmful mutations in any of these genes disable the gene or the protein that it produces.
Specific inherited mutations in BRCA1 and BRCA2 increase the risk of female breast and
ovarian cancers, and they have been associated with increased risks of several additional types
of cancer. Together, BRCA1 and BRCA2 mutations account for about 20 to 25 percent of
hereditary breast cancers (1) and about 5 to 10 percent of all breast cancers (2). In addition,
mutations in BRCA1 and BRCA2 account for around 15 percent of ovarian cancers overall (3).
Breast and ovarian cancers associated with BRCA1 and BRCA2 mutations tend to develop at
younger ages than their nonhereditary counterparts.
Breast cancer: About 12 percent of women in the general population will develop breast cancer
sometime during their lives (4). By contrast, according to the most recent estimates, 55 to 65
percent of women who inherit a harmful BRCA1 mutation and around 45 percent of women who
inherit a harmful BRCA2 mutation will develop breast cancer by age 70 years (5, 6).
Ovarian cancer: About 1.3 percent of women in the general population will develop ovarian
cancer sometime during their lives (4). By contrast, according to the most recent estimates, 39
percent of women who inherit a harmful BRCA1 mutation (5, 6) and 11 to 17 percent of women
who inherit a harmful BRCA2 mutation will develop ovarian cancer by age 70 years (5, 6).
Mutations in BRCA1 and BRCA2 increase the risk of several cancers in addition to breast and
ovarian cancer. BRCA1 mutations may increase a woman’s risk of developing fallopian tube
cancer and peritoneal cancer (7, 8). Men with BRCA2 mutations, and to a lesser extent BRCA1
mutations, are also at increased risk of breast cancer (9). Men with harmful BRCA1 or BRCA2
mutations have a higher risk of prostate cancer (10). Men and women with BRCA1 or BRCA2
mutations may be at increased risk of pancreatic cancer (11).
Relative indications for testing for a mutation in BRCA1 or BRCA2 for newly diagnosed or family
members include a family history among 1st (FDR), 2nd (SDR), or 3rd(TDR) degree relatives
usually on the same side of the family but not limited:[12]
- A known mutation (BRCA1 or BRCA2) in a cancer susceptibility gene within the family
- Women affected with any Breast cancer diagnosed under the age of 30[14]Women affected
with triple negative breast cancer (TNBC) (estrogen receptor negative, progesterone receptor
negative, and HER2/neu negative) under the age of 50
- Two relatives (FDR/SDR) diagnosed under the age of 45
- Three relatives (FDR/SDR) diagnosed with average age of 50 or less
- Four relatives at any ages
- Ovarian cancer with either an additional diagnosed relative or a relative with male breast
cancer
- A single family member with both breast and ovarian cancer
- Male breast cancer
- Pancreatic cancer with breast or ovarian cancer in the same individual or on the same side of
the family.
INTENDED USE
Oncogenetics BRCA Panel Kit is intended for detection and allelic discrimination of 8
mutations of BRCA genes: BRCA1 (185delAG, 4153delA, 5382insC, 3819delGTAAA,
3875delGTCT, T181G (Cys61Gly), 2080delA) e BRCA2 (6174delT). These mutations increase
the risk of breast and ovarian cancers, and they have been associated with increased risks of
several additional types of cancer.
PRINCIPLE OF ASSAY
Oncogenetics BRCA Panel Kit is a qualitative tests that allow the detection by Real Time PCR
based on the amplification of the genome specific region using specific primers. In Real Time
PCR the amplified product is detected using fluorescent dyes. These dyes are linked to
oligonucleotide probes that bind specifically to the amplified product. The real-time monitoring of
the fluorescence intensities during the reaction allows the detection of accumulating product
without re-opening of the reaction tubes after the PCR run.