Genes and Heredity
A gene is the basic unit of heredity in a living organism, and is made up of DNA. Heredity is the transfer of characteristics from parent to offspring through their genes. Living organisms pass their DNA, as encoded instructions, to their offspring. Half of our genetic code comes from our father and the other half from our mother.
Genes are carried in chromosomes. Each human cell has 46 chromosomes. Each chromosome contains up to 3,000 genes. Some contain less, like the Y-chromosome that only has 231 genes. But not all genes in a chromosome work; some are “turned on” and others “turned off.” In the human, only 2% of all genes should be “turned on.”
Genes are made up of segments of DNA. A gene is a DNA sequence with coding instructions for a particular protein. Through the DNA, genes encode instructions to make many different types of proteins within our living cells. The human body needs proteins for growth and development. Proteins are necessary to build muscles, bones, blood, hormones, and all other types of tissue and fluid in our bodies. Certain types of proteins, called enzymes are manufactured by genes and control many cellular activities within our bodies. More information is available at this link:
Genetics and Genomics
Genetics is the study of the way physical traits and characteristics get passed down from one generation to the next. Genetics includes the study of genes, which determine what you will look like and whether you are likely to have certain illnesses.
Genomics is a new science that includes the complete study of the hereditary material of living beings and its relationship with the environment.
Sometimes, when genes are abnormal or have been changed by a mutation, they may not work properly, which may lead to disease. Some genetic abnormalities, or “gene mutations,” are passed on from parent to child. Other genetic conditions are not inherited. Sometimes a gene mutation alone can cause a person to have a disease, but most diseases are caused by a combination of genetic and environmental factors.
Some genetic conditions are said to “run in families”, with several family members having the same condition. Other genetic conditions only occur in one family member.
More information is available at these link Genetic Disease Information and Genetic Disorders
Genetic screening and testing
There are many types of genetic tests. Some will let you know if you have a particular condition or disorder, while others may show if you have inherited a tendency to get certain diseases. A sample of blood, skin or other tissue is needed for genetic testing. Testing for gene mutations is available for many inherited diseases. Researchers continue to develop new tests.
More information on genetic testing and screening can be found at these links: FAQ and Genetic Testing and Genetic Home Reference