genetics

Genetics is the study of heredity, the process in which a parent passes certain genes onto their children. A person's appearance -- height, hair color, skin color, and eye color -- are determined by genes. Other characteristics affected by heredity:

• Likelihood of getting certain diseases
• Mental abilities
• Natural talents

An abnormal trait (anomaly) passed down through families (inherited) may:

• Have no effect on your health or well being -- for example, it may just involve a white patch of hair or an extended earlobe
• Be of minor consequence -- for example, color blindness
• Have a dramatic effect on your quality or length of life

For most genetic disorders, genetic counseling is advised. Many people may also want to seek prenatal diagnosis.

The terms anomaly, abnormality, disorder, defect, disease, and syndrome are not used consistently, and do not have precise definitions.