Hereditary disease, from radiation

In the study of the mechanism of hereditary disease production, it is not possible to separate gene alteration from environmental effects on the genetic material. Indeed, most if not all chromosomal (or DNA) alterations that are transmitted from parent to progeny may have resulted from environmental injuries. A number of environmental factors known to injure chromosomes are ionizing and ultraviolet radiation, viruses, chemicals—including drugs, and vitamin deficiencies. 

Such late effects might be the development of malignant (cancerous) diseases and of the hereditary consequences. Here, it has to be mentioned that in human populations, hereditary effects could not be detected even in the offspring of the large population of A-bomb survivors in the first two generations. The possibility of hereditary alterations is known only from experimental observations in radiation biology. 

There are two main types of cataracts. One type, which occurs during development, results from hereditary, nutritional, or inflammatory processes that interfere with the normal growth of the lens. The other is degenerative and is due to retrogressive changes in the developed lens it accompanies senility, systemic diseases, radiation injury, and trauma. 

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