Читать книгу Lifespan Development - Tara L. Kuther - Страница 120

Not all inborn characteristics are inherited. Some result from mutations, sudden changes and abnormalities in the structure of genes that occur spontaneously or may be induced by exposure to environmental toxins such as radiation and agricultural chemicals in food (Lewis, 2017). A mutation may involve only one gene or many. It is estimated that as many as one half of all conceptions include mutated chromosomes (Plomin et al., 2013). Most mutations are fatal—the developing organism often dies very soon after conception, often before the woman knows she is pregnant (Sadler, 2015).