Genetic testing

• By DEBRA LEMOINE
• Published: Dec 28, 2008 - UPDATED: 12:05 a.m.

• Print
• Email
• Save
• Twitter
• Social Media

• Del.icio.us
• Digg
• Facebook
• Reddit
• 

Lori Dumaine was diagnosed with an early-stage breast cancer at age 39, nearly a decade after her older sister died of the disease at age 32.

Because of this family history and Dumaine’s young age for developing the cancer, Dumaine’s doctor recommended that she take a test to determine if she has a specific genetic mutation that predisposes her to breast cancer.

A month into her cancer treatment, the results came back positive. She had BRCA1, or breast cancer 1, one of the two known hereditary gene mutations for breast cancer. The other mutation is known as BRCA2.

“It really affected how we would treat the cancer,” Dumaine said.

Typically, Dumaine, now 45, would have been a candidate for breast preservation because of her young age and the early diagnosis, said Dr. Jay Brooks, an oncologist with Ochsner Health Center in Baton Rouge.

However, the known genetic mutation put her at a greater risk of the cancer’s returning, so she had both breasts and both ovaries removed, Brooks said.

Genetic testing is an emerging tool in preventing and treating such diseases as cancer. Patients can be tested to see if they inherited a specific genetic mutation in their cells that leads to breast, colon and skin cancers.

Even newer, and often controversial, tests are being developed to see if normal differences in a person’s genetic makeup raises or lowers the risk of developing such diseases as Type 2 diabetes or prostate cancer.

Essentially, cancer is a malfunction in normal cell growth, said Dr. Duane Superneau, director of Genetic Services of Louisiana in Baton Rouge.

Cancer occurs when a cell makes a mistake, known as a mutation, in copying its own genetic information in order to grow new cells. New cells then continue to form from this incorrect genetic information.

Most cancer, 90 to 95 percent of it, is caused by these random mistakes in cell replication, Superneau said.

But some people, such as Dumaine, inherited a mutation in their genetic code that predisposes them to developing certain types of cancer, Superneau said. For every woman who develops breast cancer, about 1 in 10 have one of the known gene mutations for this disease.