ABSTRACT
The pathologist may also diagnose genetic disorders by the use of special stains to demonstrate abnormal cellular products and cancer, now known to be hereditary in some cases, is diagnosed by the pathologist on a routine basis. The main limitation of Morgan’s work was the infrequency of spontaneous genetic mutation. His student Herman Muller showed that X-rays could cause mutations, but at a greatly accelerated rate. Genes, the working units within chromosomes, are the special sequences of codons in DNA that code for proteins. Most of the remaining chromosomal material has no known function and can be likened to junk mail. Autosomal dominant conditions are passed from parent to child with each child having a 50% chance of inheriting the altered gene. Such conditions are therefore easy to recognise, particularly because they are often associated with obvious physical and/or mental changes.
