Research suggests link between infertility, low egg reserve, and mutations in breast/ovarian cancer gene (BRCA1)
New findings may help explain why women who carry a mutated
BRCA1 gene have greater rates of infertility as well as a greater risk for breast
and ovarian cancer
A New York Medical College physician who specializes in restoring or preserving
fertility in female cancer patients has discovered a possible link between the
presence of breast cancer genes and infertility.
In a paper published in the Journal of Clinical Oncology,
Kutluk Oktay, M.D., professor of obstetrics and gynecology and principal investigator
on the study, concluded that mutations in the BRCA1 gene, which have been linked
with early onset breast cancer, are also associated with an early loss of egg
reserves. This finding may help to explain why women who carry a mutated BRCA1
gene have greater rates of infertility as well as a greater risk for breast and
ovarian cancer.
Dr. Oktay's team performed ovarian stimulation in 126
women with breast cancer for the purpose of fertility preservation by embryo or
oocyte cryopreservation. The results showed that of the 82 women who met the inclusion
criteria, 47 women (57 percent) had undergone BRCA testing, with 14 having a mutation
in BRCA genes. In BRCA mutation-positive patients, the low ovarian response rate
was significantly greater than for patients who did not show BRCA gene mutations,
nor for women who had not been tested for the gene at all.
If fertility drugs are not as effective in stimulating
egg production in the ovaries of patients who carry BRCA1 mutations, this establishes
a link between infertility and the risk of getting breast or ovarian cancer, Dr.
Oktay concludes.
It is estimated that in the general population, one in
every 1,000 women is BRCA mutation positive, with the incidence as high as 2.5
percent in certain ethnic groups such as Ashkenazi Jews. Researchers have identified
hundreds of mutations in the BRCA1 gene, many already associated with an increased
risk of cancer. This means that the mutations in BRCA1 gene may affect egg reserve
and fertility of a significant number of women in the U.S.
In addition to his appointment in the Department of Obstetrics
and Gynecology, Dr. Oktay is professor of cell biology and anatomy, and professor
of medicine. He is director of the Division of Reproductive Medicine and Infertility,
and also directs the Laboratory of Molecular Reproduction and Fertility Preservation
in the Department of Obstetrics and Gynecology at Westchester Medical Center in
Valhalla, N.Y.
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