Pigmentation of lips in Peutz-Jeghers syndrome. Development of cancer is related to both environmental carcinogens and genetic predisposition. Though the risk of a common cancer occurring in relatives ofan affected person is generally low, familial aggregations that cannot be explained by environmental factors alone exist in some O neoplasms, such as breast and ovarian cancers and melanomas. In...

Pneumoviruses are responsible for significant respiratory disease in their hosts and represent a major problemfor human and animal health. Pneumoviruses are members of the family Paramyxoviridae, subfamilyPneumovirinae and the virus particles consist of a negative-sense, nonsegmented RNA genome within a helical nucleocapsid structure enveloped in a lipid membrane derived from the ho...