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In this case, developed for an introductory genetics class, students meet a woman whose family has a history of colon cancer. Students create a pedigree based on information from the case and discuss what it means to be genetically predisposed to cancer. Using bioinformatics tools from the NCBI database, students identify and examine the mutation in the woman's APC gene that results in genetic predisposition to colon cancer. Finally, they investigate the biological function of the APC protein to understand why this mutation contributes to the development of cancer and determine whether APC is a proto-oncogene, tumor suppressor gene, or genome stability gene.

Most colon cancers may be caused by infections with bacteria that are normally found in cows. For decades we have known that Streptococcus gallolyticus gallolyticus (SGG) is sometimes found in colon tumours, but now the microbes have been found to directly cause tumour growth in mice.

New immune system-boosting cancer drugs have in clinical trials saved the lives of many people with seemingly untreatable melanoma or lung cancer, but the drugs seem useless against colon cancer. One exception-a man with colon cancer whose metastatic tumors vanished for several years after he was treated in 2007-piqued researchers' interest. They suspected his recovery might have to do with the large number of mutations in his tumors. Now, a small clinical trial suggests that even cancer patients with types of tumors that were thought to be impervious to the new drugs could benefit if those malignancies have the right error-riddled DNA signature, a result that could help 3% to 4% of cancer patients.

Researchers at the University of Pennsylvania performed "stress tests" on pregnant mice using a predator's odor, restraint, or unfamiliar noises. After the mice gave birth, the scientists analyzed the bacterial communities in their vaginas and in their pups' colons. The researchers found that stress during pregnancy altered the expression levels of several proteins involved in vaginal immunity and the frequency of Lactobacillus bacteria, which, expectedly, correlated to lower frequencies of Lactobacillus within their pups' gut microbiomes. Male pups of stressed mothers also displayed an increase in anaerobic bacteria like Clostridium and Bacteroidesin.

2:40 video The anole lizards of the Caribbean islands represent a group of about 150 closely related species, most of which evolved within the past 50 million years from a single colonizing species.

The anole lizards of the Caribbean islands represent a group of about 150 closely related species, most of which evolved within the past 50 million years from a single colonizing species. Different processes, including geographic isolation, adaptation to different environments, and reproductive isolation, play a role in anole speciation. 

The human large intestine (colon), in healthy individuals, has extremely low oxygen concentrations, and over 90% of its microbiota are strict anaerobes. Researchers taking metagenomic fecal microbiota surveys of adult Europeans could assign about 0.8% of the genes in their dataset to archaea [9], and similar numbers (0.2%-0.3%) were reported for Amerindians and Malwaians [10], while North Americans had much lower fractions (<0.05%).

WEDNESDAY, April 22, 2015 (HealthDay News) -- In a step toward personalized vaccines against cancer, scientists report they have developed an immune-system therapy that knocks out several types of aggressive tumors in mice. German researchers said the findings, reported April 22 in the journal Nature, could lead to a "blueprint" for developing tailored vaccines for a range of cancers. Such vaccines would be designed for individual patients, based on the specific genetic mutations in their tumors.