Skin color in humans, many genes determine the skin color and offspring is expected to express an intermediate phenotype…
•The Merle gene creates mottled patches of color in a solid color coat, blue or odd-colored eyes, and can affect skin pigment as well.…
In addition to genes, we also have melanin that is present in our bodies that is a determining factor in the color of our hair, skin and eyes. While everyone has melanin in their cells, the amount from person to person is not equal. The more melanin present in your skin, the darker your complexion will be. The different types of melanin present in the iris produce pigmentation there, and these factors are largely dependent…
sporadic new mutation, which happens at conception. Therefore, as mentioned above, the diagnosis must be made…
Most skin cancer are caused by sun exposure. Exposure to some chemicals and in rare cases the abnormal genes that cause skin cancer can be inherited by children from their parents…
Some blood disorders can be prevented while there are others that are out of a person’s hands and have to live with a blood disorder for a life time. It is essential to know the causes of hereditary disease and know how to treat them. It is also important to know what can be done to “cure” other blood disorders and what preventive measures need to be taken in order to stop history from repeating itself. Iron deficiency anemia, sickle cell anemia, and purpura simplex are just a few blood disorders that people suffer from that are either inherited or can be prevented.…
Melanin is the pigment in the skin that absorbs ultraviolet light and protects the skin from sun damage, so the less pigment in a person’s skin the less protection they have from ultraviolet light. So light skinned people (Caucasians), particularly those with light coloured eyes and light coloured hair are more susceptible to sun damage and skin cancer than people with more pigment in their skin. People, who have no melanin at all, like people with albinism or vitiligo, are much more susceptible to skin cancer.…
Other kinds of genes create differences among people. Children’s eye color, and facial appearance are largely determined by genes.…
Give an example of a dominant and recessive genetic disorder. People with light eyes tend to carry recessive alleles of the major genes; people with dark eyes tend to carry dominant alleles.…
Vitiligo is a disorder that causes the destruction of melanocytes. It has three important factors underlying this destruction. The depigmented skin has many aberrant functions such as a muted response to contact allergens, a phenomenon also seen in mice that depigment. The white skin of those with vitiligo does not form non-melanoma skin cancers although the white skin of albinos, which has a similar color as vitiligo, is highly susceptible to skin cancer.…
There are several factors that contribute to the cause of BCC. These factors include, light colored skin, light colored eyes, blonde or red hair, overexposure to x-rays or radiation, many moles, genetics, many severe sunburns early in life, and long term daily sun exposure (Medline Plus, 2012). Individuals with light colored skin, hair, and eyes have poor tanning abilities and are more likely to have sun-damaged skin (Roewart-Hober, 2007). Radiation therapy in childhood for ringworm on a 58 year old patient caused an aggressively growing BCC that took over most of the posterior scalp (Asilian, 2005). Genetics also contribute to your likelihood of getting a BCC. A family history of skin cancer can increase your chances of having a BCC (Skelton, 2009). Also, there is several inherited and acquired skin disorders associated with BCC. These disorders include xeroderma pigmentosum, nevoid basal cell syndrome, Bazex-syndrome, Rasmussen syndrome, Rombo syndrome, and albinism (Roewert-Hober, 2007). Although there are several contributing factors to BCC, the number one cause is sun exposure and other ultraviolet…
Moalem suggests that all humans had pale skin with dark hair all over to protect ourselves from too much sunlight. However, as the human evolved and lost a significant amount body hair, the skin, the largest organ of the body, would become exposed to the strong ultraviolet rays of the sun. Ultraviolet B, a specific type of ultraviolet light, is beneficial as it effectively converts our cholesterol into Vitamin D, which the body cannot simply live without. However, too much sunlight exposure and harmful effects quickly outnumber the beneficial ones, ranging from sunburn to skin cancer and the decrease of our body's folic acid. Thus, humans, especially those near the equator, developed a darker skin tone with the pigment melanin. While the color of the dark skin absorbs more heat and light, the melanin in the skin prevents too much of the harmful rays from penetrating the skin, protecting folic acid. However, "[dark skin] didn't evolve with a switch -- you can't turn it off when you need to whip up a batch of vitamin D." That is where the genetic mutation apolipoprotein E, or ApoE4 for short, came in. "[ApoE4] ensures that the amount of cholesterol flowing through your blood is cranked up. With more cholesterol available for conversion, dark-skinned people can maximize the use of whatever sunlight penetrates their skin." The fair-skinned Europeans of the time…
Color blindness is usually inherited but you can get it other ways. Color blindness can also happen if physical or chemical damage is done to the eye, the optic nerve, or parts of the brain. The gene that produces photopigment is on the X chromosome. The X chromosome is sex-linked which is why color blindness usually is more dominant in males. Males have only one X chromosome. If this gene is…
In the first case, Melanie Gaydos, from New York, was born with a genetic condition called ectodermal dysplasia. Ectodermal Dysplasia is a genetic condition that develops when clumps of cells become specialized cells, but in Melanie's case, her cells didn't do that. When the different layers of cells…
How do children inherit eye color? Can a child's eye color be predicted? Why are an albino's eyes pink? How can two brown eyed parents produce a blue eyed child? Why are my eyes a darker blue than my sibling's? How are the colors in the iris formed? These are questions one may have wondered from time to time. The answer to all of these questions lies in the genes inherited from a one's parents.…