Mutations

All her life, Lindsay Shipp knew that she was dying. As a baby, she would cry after eating, and salt collected on her forehead. The diagnosis was cystic fibrosis, an incurable genetic disease that, at the time, meant a life expectancy of 18 years. The disease, which affects 30,000 people in the United States, hinders the movement of salt in the body. Because of this, the pancreas fails soon after birth, patients cannot properly digest food, and their airways fill with mucus, leaving them vulnerable to lung infections and other problems.

With good reason, most contemporary economists regard Adam Smith as the founder of their discipline. But I would instead accord that honor to Charles Darwin, the pioneering naturalist. Although Darwin had no formal training in economics, he studied the works of early economists carefully, and the plants and animals that were his focus were embroiled in competitive struggles much like the ones we see in the marketplace. His observations forged an understanding of competition that is subtly but profoundly different from Smith's.

Having mutations in the BRCA1 or BRCA2 genes lead to a higher risk of breast and ovarian cancers in women, but the mutations don't affect health outcomes in exactly the same way. A team led by researchers from the University of Texas M.D. Anderson Cancer Center in Houston reported Tuesday that having a mutated BRCA2 gene was associated with improved survival and chemotherapy response among a group of women with ovarian cancer.   In fact, women with BRCA2 mutations had better survival after treatment than women without mutations on either gene, the group wrote in a study published in JAMA, the Journal of the American Medical Assn.

Women who inherit gene mutations that increase their likelihood of getting breast cancer now face an added worry: They may be prone to developing the disease earlier in life than their mothers and aunts did. The discovery, by a team at the University of Texas M.D. Anderson Cancer Center in Houston, was reported Monday in the journal Cancer. Harmful mutations in the BRCA 1 and BRCA 2 genes dramatically increase a woman's chance of developing breast and/orovarian cancer, according to this fact sheet from the National Cancer Institute.  About 60% of women with a harmful mutation in BRCA 1 or BRCA 2 will develop breast cancer sometime during their lives.  In the general population, about 12%of women will.  BRCA mutations are responsible for 5% to 10% of breast cancer diagnoses.

The risk of a family with one autistic child having another child with autism is double what was previously thought, according to a new study. The findings, published in the journal Pediatrics, are of average risks, scientists say: They will vary according to the family's specifics. "I have seen families with five kids with autism," said Dr. Fred Volkmar, a child psychiatrist and autism expert at Yale University. Volkmar was not part of the study, published Monday. Scientists have long known that autism runs in families.

Autism is not caused by one or two gene defects but probably by hundreds of different mutations, many of which arise spontaneously, according to research that examined the genetic underpinnings of the disorder in more than 1,000 families. The findings, reported in three studies published Wednesday in the journal Neuron, cast autism disorders as genetically very complex, involving many potential changes in DNA that may produce, essentially, different forms of autism. The affected genes, however, appear to be part of a large network involved in controlling the development of synapses, the critical junctions between nerve cells that allow them to communicate, according to one of the three studies.

Autism spectrum disorders can be caused by as many as 300 or so rare genetic mutations, scientists reported Wednesday. The research strongly implicates genetics, including spontaneous gene mutations, in the development of the disorder. But why do four times as many males as females develop autism spectrum disorder? In one of the three papers published in the journal Neuron , researchers suggest that girls are more resistant to gene mutations than boys. Girls seem to require a higher number of gene mutations to become afflicted with autism spectrum disorder.

An experimental drug called crizotinib sharply increases survival in lung cancer patients with a specific genetic mutation, researchers said Sunday. Although only about 4% of lung cancer patients carry the mutation, that still amounts to about 50,000 people worldwide, experts said. Researchers hope that other new drugs targeted at different mutations will be also developed and that combinations of such targeted drugs will prove even more effective in lung cancer. Lung cancer is the second-most-common form of cancer in the United States and the biggest cancer killer among both men and women, with 371,000 cases diagnosed each year and 159,000 deaths.

In the new movie "X-Men: First Class," a group of normal-looking people with some highly unusual traits wonder if the world will embrace them. The studio behind the film, 20th Century Fox, is facing a similar question. Although the fifth installment in the franchise about superhero mutants resembles many of Hollywood's summer offerings — a big-budget action movie based on a popular comic book series — the latest "X-Men" is a vastly different creature that presents some unique marketing challenges.

Two studies released Wednesday by the journal Nature show that work remains before so-called induced pluripotent stem (iPS) cells are ready for use in laboratory studies or clinical therapies. iPS cells are body cells that are programmed to unwind back into an embryonic state.  Like embryonic stem cells, they have potential to develop into any other type of cell in the body. But they don't reprogram perfectly, researchers are showing.  About a month ago, a team at the Salk Institute showed that iPS cells hold on to "memory" of their past identity.