The isolated western Java village of Ciburuy has possibly one of the highest rates of albinism in Indonesia, and nobody seems to know why. Nana Suryana always knew he had albino ancestors. His great-grandfather was a “white man” and his family has lived in the same village of Ciburuy, in western Java, for centuries. For a child to be albino, both parents must carry a gene — and any child born to such parents will have a one-in-four chance of albinism even when both parents have normal pigmentation.

Sure enough, Nana Suryana and Siti Rohma’s youngest child, two-year-old Jajang Gunawan, is also albino. A third child who died at birth was not. But what makes the village of Ciburuy so remarkable is that it is not just one or two families that carry an albino gene. There are clearly many more “carriers” in this small village than for the average population.

“We’ve been here for 149 generations. My family is famous for having the white gene,” he says. What he did not know when he married Siti Rohma was that she too carried a gene for albinism. When their daughter Dewi Rasmana was born — with white hair and skin, and pale blue eyes — both parents assumed her albinism came from her father’s side of the family. When she gave birth, the child was white-haired and white-skinned. Since then, every few generations, more white-skinned children have followed.

Nana Suryana and Siti Rohma’s family of five. Today there are 10 people in the village with albinism — and others who have moved away — from a population of just a few hundred people.

The rare case of Albinism in humans is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes. Albinism is associated with a number of vision defects, such as photophobianystagmus, and amblyopia. Lack of skin pigmentation makes for more susceptibility to sunburn and skin cancers. In rare cases such as Chédiak–Higashi syndrome, albinism may be associated with deficiencies in the transportation of melanin granules. This also affects essential granules present in immune cells leading to increased susceptibility to infection.

The incidence of albinism is much higher in parts of Africa, where as many as one in 3,000—5,000 people have the condition. In pockets of the South Pacific, the incidence is higher again — as many as one in 500. And at Ciburuy, the rate appears to be even higher, though villagers say they are unaware of any formal study.

The social stigma of being and looking different, particularly in a culture where skin tone is universally darker, has also exposed many to teasing or bullying. Albinism results from inheritance of recessive gene alleles and is known to affect all vertebrates, including humans. It is due to absence or defect of tyrosinase, a copper-containing enzyme involved in the production of melanin. It is the opposite of melanism. Unlike humans, other animals have multiple pigments and for these, albinism is considered to be a hereditary condition characterized by the absence of melanin in particular, in the eyes, skin, hair, scales, feathers or cuticle. While an organism with complete absence of melanin is called an albino, an organism with only a diminished amount of melanin is described as leucistic or albinoid. The term is from the Latin albus, “white”.

Nana Suryana’s niece Rosanah, now 20, says she had to leave school early because she was bullied by classmates over her white skin. She can’t find work because she didn’t finish school, and works mostly at home. She now doesn’t know if she wants to get married and have children of her own, because of the fear that they too may have the condition. “Sometimes it’s hard being white. I was often teased at school. I was often upset because of it,” she says.

Today albinos at Ciburuy are known as Walanda Sunda, or Sundanese white people. Like those with albinism anywhere, the Walanda Sunda at Ciburuy have extreme sensitivity to the sun because of the lack of melanin in their skin, and a correspondingly high risk of skin cancer.

Nana Suryana’s 14-year-old daughter Dewi Rasmana has had an easier time. She is still at school and says she has had little experience of being teased for being different — though she regularly has to cover up against the sun, and her eyesight is worsening as she gets older. Poor schooling and poverty in a village like Ciburuy can also limit the education of a child with albinism.A couple of streets away, 40-year-old Suryana works outdoors on a building site. He wears long sleeves, sunglasses and a cap to cover his skin against the sun.

Even the cost of sunscreen in a village like Ciburuy is prohibitive. But Dr Parker says persecution of albinos is worst in many African countries, where they are considered non-human, even ghosts. Superstition in Tanzania for example has seen many albino people murdered so their body parts can be used in witchcraft. It is suggested that the early hominin evolved in East Africa around 3 million years ago.

 The dramatic phenotypic change from primate to early hominin is hypothesized to have involved the extreme loss of body hair – except for areas most exposed to UV radiation, such as the head – to allow for more efficient thermoregulation in the early hunter-gatherers. The skin that would have been exposed upon general body hair loss in these early hominins would have most likely been non-pigmented, reflecting the pale skin underlying the hair of our chimpanzee relatives.

A positive advantage would have been conferred to early hominids inhabiting the African continent that were capable of producing darker skin – those who first expressed the eumelanin-producing MC1R allele – which protected them from harmful epithelium-damaging ultraviolet rays. Over time, the advantage conferred to those with darker skin may have led to the prevalence of darker skin on the continent. The positive advantage, however, would have had to be strong enough so as to produce a significantly higher reproductive fitness in those who produced more melanin. The cause of a selective pressure strong enough to cause this shift is an area of much debate. Some hypotheses include the existence of significantly lower reproductive fitness in people with less melanin due to lethal skin cancer, lethal kidney disease due to excess vitamin D formation in the skin of people with less melanin, or simply natural selection due to mate preference and sexual selection.

Compared to Indonesia’s Ciburuy village, the average life expectancy for someone with albinism in Tanzania is about 30, because of the combined risks of skin cancer and attacks.


Source By Anne Barker with pictures from Phil Hemingway

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