Skin The Wonderwrap-2

The skin colors vary in man to a great deal. We see in any cosmopolitan city people with complexions ranging from ebony black to milky white. The human skin color depends mainly on a single pigment called the melanin. To some extent the skin color depends on blood circulating in the part of body too. A blush of pink and pallor of death as well as angry red are all too familiar to us.

Melanin is in cells of skin called melanocytes. They are located in epidermis, especially in the Stratum basale and in the hair follicles. Melanocytes produce the melanin. It uses the raw material - an amino acid called, tyrosine, to make the melanin.

From the melanocytes the melanin emigrates to keratinocytes. The keratinocytes arise in stratum basale and ultimately reach the stratum corneum where desquamatization i.e. removal of scales ( dead flat cells) takes place. This journey takes about 50 days for these cells. The melanin surrounds the nucleus of a keratinocyte and thus gives protection to them from ultra-violet radiation.

Exposure to sunlight has a tanning effect i.e. the sun exposed skin darkens. This is due to (a) rapid release of melanin into keratinocytes and (b) acceleration in the rate of synthesis of melanin.

The ultra-violet rays appear to promote wrong pairing of nitrogen bases in DNA strands. Especially, Thymine dimers i.e. instead of the usual pairing of Thymine with Adenine, there is a pair formed of two Thymine bases.

It is estimated that if 4 hrs are spent on a beach 10 u-v ray induced Mutations (Thymine dimers formations) would be produced. Any new skin growths or wounds or changes in appearance of a previous skin lesion, which appear unusual, itch or hurt, bleed or expand in size, should be brought to the attention of a skin specialist to rule out the possibility of skin cancers.

Since prevention is better than cure it is better to avoid or reduce the dangerous ultra-violet sun exposure. This can be done by not going out between (10 a.m. - 3 p.m.) when the sun is at its fiercest or by using effective sunscreens if, going out in the sun cannot be postponed.

People with little or no melanin in their eyes, skin, or hair are called albinos. They inherit genes that do not make the usual amounts of melanin.

Parents who have normal hair and eye color (for their ethnic backgrounds) can have children with albinism. If a child with albinism shows unusual bruising or bleeding one may suspect a form of albinism, the Hermansky-Pudlak syndrome. (Please visit for more details - http://www.albinism.org a site developed by NOAH = National Organization for Albinism and Hypopigmentation, a self-help volunteer organization for persons and families involved with albinism)

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