As a former U.S. senator from Pennsylvania has repeatedly stated that his daughter had already beaten the chances of survival of children with trisomy 18. Nearly 60 percent of babies who die from the condition in the hospital a few days after birth. Only 5 to 10 percent survive one year. Only 1 percent of them live 10 birthday, with long survival, which is much more likely to have girls.
Bell, whose full name of Isabella, who was born in 2008. The family did not provide details about his condition, although it was recently hospitalized with pneumonia would be the second time this year.
Children with trisomy 18 (sometimes also called Edwards syndrome) have three copies of chromosome 18 instead of two. Humans have 22 pairs of chromosomes, regular (so-called "autosomes") and one pair of sex chromosomes, with one half of each pair contributed by the father and half from the mother. The cause of the disease is unknown, although, as with the same defects, children with older mothers are more at risk.
Trisomy 18 is one of the three most common chromosomal abnormalities, although this rarely occurs in 1 in 8000 newborns.
It can be found before birth by microscopic examination of amniotic fluid and ultrasound. Three-quarters of the fetus diagnosed with a miscarriage or stillbirth from 12 weeks of pregnancy and childbirth. Some of them are selectively aborted.
Almost all children with trisomy 18 were multiple organ defects. Almost all have abnormal heart with a hole between the large chambers of the heart, the ventricles, the default is the most common. One-third of them have a horseshoe kidney, and one fifth were abnormal esophagus. Mental retardation is common but not universal, and many of them have distinctive facial features, such as low-set ears.
About 90 percent are underweight at birth, and some of them early, which further jeopardizes their health in the first days after birth.
Infections are common, persistent problems in children with trisomy 18 who survived.
Last year, researchers at Tufts University analyzed the genes were more or less active in fetuses with trisomy 18 than in those who do not have the disease. They found that 251 "activation" has been significantly different.
Surprisingly, only 3 per cent of these genes on chromosome 18 were. This suggests that many problems are the result of bad signals from the chromosome 18 gene is probably normal genes on other chromosomes.
Among the genes affected are those that regulate the immune system, which is probably due to an unusual susceptibility to infection in children.
Staff researcher Lucy Shackelford contributed to this report.
No comments:
Post a Comment