Genetic diseases



Genetic diseases

Introduction

Genetic conditions are important to families and individuals because they carry information about disease that can be passed on through generations from parents to children. Knowing (or not knowing) about a family history of genetic illness may be important for an individual's health, lifestyle, and psychological well-being. Those affected by genetic disorders frequently experience feelings of guilt and shame about the potential of passing on illness to their children. Research suggests that communication in families about genetic conditions is not always straightforward, with some relatives being poorly informed or even ignorant about their family history of disease.

This is an important issue because genetic testing and knowledge about genetic susceptibility have become more widely available and will be relevant to more and more people. This entry discusses some of the concerns for families and health professionals with regard to the passing on of genetic knowledge to at-risk relatives. It begins by discussing whose responsibility it is to pass on such information and the issue of nondisclosure. It moves on to outline the role of health professionals in this area and provides a summary of empirical evidence. The entry concludes by discussing the difficulties in determining and assessing successful family communication about genetic risk.

What genetic diseases or problems were determined to be potential issues?

The Human Genome Project marked a new beginning toward understanding the genetic basis of an increasing number of medical conditions. In addition to many gene-disease associations that were unveiled and characterized, significant attention was captured by the 0.1% of the genome that represents interindividual variability. Over 3 million interindividual differences at the nucleotide level, known as single nucleotide polymorphisms, were catalogued, and many of them shape predispositions to medical conditions, adverse reactions in response to therapeutic agents, or sensitivity to environmental chemicals.

More recently, an additional source of interindividual genetic variability—the deletion or duplication in varying numbers of genes or chromosomal regions as large as 3 million bases—became known as copy number variation (CNV). CNVs were linked to medical conditions such as autism spectrum disorders, schizophrenia, infectious disease susceptibility, and autoimmune diseases, but they were also described in apparently healthy individuals.

At the same time, recent years witnessed a new generation of DNA sequencing methodologies, which rely on increasingly sophisticated platforms, software, and bioinformatics tools and provide sequences with higher accuracy, at lower costs, and faster than before. Some instruments can sequence between 10 and 80 million base pairs within an hour. This marks an important step toward the $1,000 human genome, a much-anticipated milestone in the transition toward the era of personalized medicine, in which the sequencing of a human genome could be performed for $1,000, allowing individual genetic profiles to become part of prophylactic and therapeutic clinical decisions.

What mode of inheritance do you think this disease/trait follows? Why? (Explain your thinking here very thoroughly; this should take up about half of the length of the assignment).

There are several degenerative diseases of the muscles, with the most well-known being the muscular ...