Down syndrome is a common chromosomal disorder caused by an error in cell division that results in the presence of an additional third chromosome 21 or "trisomy 21".

 

The incidence of Down syndrome is estimated to be 1 in every 600 - 800 live births. It is the same in all countries, climates and social groups. It is not related to the parents’ way of life, health status, income, education, race or nationality. Boys and girls with Down syndrome are born with equal frequency in families where parents have a normal chromosome set. The presence of an odd chromosome is not anybody’s fault!

 

Down syndrome was first identified in 1866 by a British physician John Langdon Down and is named after him. Almost a hundred years later, in 1959, a French geneticist Dr. Jerome Lejeune discovered that the cells of people with Down syndrome contain 47 chromosomes, one more than the 46 that had been found, not long before, to be the normal human complement. What causes the extra chromosome has not been discovered. Today we know that Down syndrome is a genetic state which comes about at the moment of conception and is caused by a presence of an odd chromosome. A human cell ordinarily contains 46 chromosomes assorted in 23 pairs. Cell replication is related to complex modifications in the karyon, and occasional deviations may occur at conception. People with Down syndrome have an additional chromosome (“trisomy 21) in the 21^st pair. This condition is caused by a genetic deviation during meiosis and results in total 47 chromosomes in a cell. The chromosomal disorder causes delays in a child’s physical, intellectual and language development. Children affected with Down syndrome usually have learning difficulties, but non the less, the overwhelming majority of them can learn to walk, speak, play and make friends with their peers, go in for sports, study at schools – in other words, to do all the things that ordinary children do.

 

In Russia there are still a great many myths and wrong stereotypes concerning the nature and consequences of Down syndrome. People with Down syndrome are believed to be hopelessly retarded and incapable of learning. Many people think that individuals affected by Down syndrome are emotionally disturbed and incapable of a true attachment, aggressive or, on the contrary, always happy. The situation is very different in civilized countries, where such stereotypes were cast back some 20-30 years ago. Research and experience show that most people with Down syndrome have IQ’s that fall in the mild to moderate range of retardation. Some are so mildly affected that they can live independently and be gainfully employed. There is a wide variation in mental abilities, behavior and physical development in individuals with Down syndrome. Each individual has his/her own unique personality, capabilities and talents. It is obvious that individuals with Down syndrome benefit from loving homes, early intervention, appropriate medical care, special or integrated education, making friends with their peers, and positive public attitudes.