Program Success Barack Obama Special Edition - Page 23

GENE DISORDERS ► ◌ DR. CHARLES E. SIMMONS Simmons Pediatrics, Jacksonville, FL There are many disorders that a person may acquire due to defaults in genes. The consequences of these genes may appear mild or moderate, or may have severe or no apparent effect. Right after birth, or early in life, the symptoms may become obvious. Some are not discovered, however, until adult life. No matter when they arise, these defective genes have been inherited by the child from their parent. Gene disorders result in a defect in one or more of the genes that are carried on the individual chromosomes. COLOR BLINDNESS ALBINISM Albinism is a disorder characterized by a lack of the brown pigment called Melanin. An affected individual may have no pigment in the hair, skin, and eyes. The hair is usually white; the skin is pale, and eyes range from pink to very pale blue. The eyes are very sensitive to bright light and visual impairment is common. Albinism is caused by a recessive gene, which means that a child has to inherit a defective gene from each parent. The gene causes a fault in the enzyme that is responsible for melanin production. Medical Student Huntington’s Disease A person who is color blind finds it more difficult to disti guish between the colors red and green, or the less common blue and yellow pair because of a defect in the cones in the retina of the eye. The disorder is inherited by a faulty gene carried on the X chromosome. Usually males are the victims of being color blind because they have only one X chromosome, and the defect carried is more likely to be expressed. A female has two X chromosomes, and a fault on one chrome some will be overridden by the other chromosome. Therefore, the female becomes the carrier and never will experience the color blindness, only males. This type of inheritance is called the X-linked recessive, and there is a 25% chance that a male will be affected. Assisted By Dominique D. Barrs Huntington’s disease causes involuntary movements, personality changes, and progressive dementia. This is one disorder that symptoms usually don’t develop until over the age of 30 because deterioration occurs over the span of 15- 20 years. Huntington’s disease is caused by an abnormal dominant gene, therefore each child has a 1 in 2 chance (50%) of inheriting the faulty gene. Sickle Cell Anemia Hemoglobin, the pigment that gives red blood cells their color, carries oxygen in the blood. When hemoglobin is deficient or abnormal, the term anemia is used. Therefore, there is a lack of oxygen being supplied to body tissues. There are many forms of anemia, but one found in people of color is the sickle-cell disease, in which the red blood cells are distorted into a curved sickle shape. A comparison between the defected sequence and the normal sequence determines the nature of the amino acid error. This was the way that the molecular basis of Sickle Cell Anemia was determined, now known to result from a Valine to Glutamine Acid substitution in position 6 of the beta-globin. GENE DISORDERS result in a defect in one or more of the genes that are carried on the individual chromosomes It is vitally important for a mother to receive the proper prenatal and postnatal care to fully understand the risks in possible future generations. Genes are inherited and it is always helpful to be aware of what genes both the mother and father can give to the offspring. Therefore, the precautions and proper care can be administered. PROGRAM SUCCESS MAGAZINE PAGE: TATYANA MAGAZINE PAGE: 23 | 23 | JANUARY MAY 2014 2015