We may look back on 2009 as the year human genome sequencing finally became routine enough to generate useful medical information (“A Turning Point for Personal Genomes”). The number of sequenced and published genomes shot up from two or three to approximately nine, with another 40 or so genomes sequenced but not yet published. In a few cases, scientists have already found the genetic cause of a disorder by sequencing an affected person’s genome.
Scientists have also sequenced the genomes of a number of cancers, comparing that sequence to patients’ normal genome to find the genetic mistakes that might have caused the cells to become cancerous and to metastasize (“Sequencing Tumors to Target Treatment”). The results suggest that even low-grade and medium-grade tumors can be genetically heterogeneous, which could be problematic for molecularly targeted drugs. That points to a need to develop new strategies for drug development and treatment in cancer.
The year brought more good news for aging mice, and maybe humans, too, as scientists identified the first drug that can extend lifespan in mammals (“First Drug Shown to Extend Lifespan in Mammals”). Rapamycin, an antifungal drug currently used to prevent rejection of organ transplants, was found to boost longevity 9 to 13 percent even when it was given to mice that were the mouse equivalent of 60 years old. Previously, genetic engineering and caloric restriction–a nutritionally complete but very low-calorie diet–were the only proven methods of extending lifespan in mammals (“A Clue to Living Longer”).
Because of its potent immunosuppressant effect, the drug isn’t suitable for this application in humans. But researchers have already found that disrupting part of the same signaling pathway has similar life-extending benefits (“Genetic Fountain of Youth”). Mice with the relevant protein disabled showed superior motor skills, stronger bones, and better insulin sensitivity when they reached mouse middle age. Female mice lived about 20 percent longer than their unaltered counterparts. But male mice, while healthy, didn’t have longer lifespans. (In comparison, caloric restriction boosts longevity by about 50 percent.) Scientists now aim to develop drugs that target this pathway, which is thought to act as a kind of gauge for the amount of food available in the environment.
The emergence in April of a new pandemic flu strain, H1N1, rapidly renewed interest in new approaches to making vaccines (“New Vaccines for Swine Flu”). For the first time during an active pandemic, pharmaceutical companies were able to use faster cell-based production methods to create vaccines against the virus, in addition to the traditional egg-based method. (None of these methods has yet been approved for use in the United States–the vaccine currently available was made in eggs.) In November, an advisory panel for the U.S. Food and Drug Administration declared that a novel method of producing flu vaccines in insect cells, while effective, needs more safety testing before it can be approved (“Caterpillar Flu Vaccine Delayed”). The vaccine, developed by Protein Sciences, based in Meriden, CT, uses a single protein from the virus to induce immunity, rather than a dead or weakened version of the virus. Two other companies began clinical trials of flu vaccines made from virus-like particles–protein shells that look just like viruses but do not contain viral DNA (“Delivering a Virus Imposter Quicker”).