NEET BIOLOGY

Detailed explanation-1: -Ocular albinism type 1 results from mutations in the GPR143 gene. This gene provides instructions for making a protein that plays a role in pigmentation of the eyes and skin. It helps control the growth of melanosomes, which are cellular structures that produce and store a pigment called melanin.

Detailed explanation-2: -OCA2, or P gene albinism, results from a genetic defect in the P protein that helps the tyrosinase enzyme to function. People with OCA2 make a minimal amount of melanin pigment and can have hair color ranging from very light blond to brown.

Detailed explanation-3: -Albinism is caused by deficiency ofmelanin, the main pigment of the skin and eye (Table 103.1). Melanin is synthesized by melanocytes from tyrosine in a membrane-bound intracellular organelle, the melanosome.

Detailed explanation-4: -Albinism affects the production of melanin, the pigment that colours skin, hair and eyes. It’s a lifelong condition, but it does not get worse over time. People with albinism have a reduced amount of melanin, or no melanin at all. This can affect their colouring and their eyesight.

Detailed explanation-5: -Melanin is a photoprotective pigment in the skin that absorbs UV light from the sun, thereby preventing skin damage. With sun exposure, the skin normally tans as a result of increased melanin pigment in the skin. However, many albinos are sensitive to sunlight and develop a sunburn because of the lack of melanin.