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Can they truly be fixed?
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Some birth defects can be possibly fixed or altered by using
embryo screening.
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Some birth defects can
possibly be fixed or altered by using embryo screening
The most common disorder known as Down’s
syndrome and contains an extra chromosome 21. Other common aneuploidies are Klinefelter syndrome (XXY), trisomy 13, and trisomy
18. Missing or having an extra chromosome can include physical and mental retardation. |
As women gets older, the chances of producing abnormal embryos
increases steadily - and experts believe that screening might be a way to improve the fertility of older women
After the age of 35, the risk of giving birth to a child with Down’s
syndrome dramatically increases.
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Some Sex-lined conditions include:
- Fragile X syndrome (one of the most common genetic diseases and the single most common cause of learning
disability; 1 in 2000 males are affected. Females may have some protection from the gene on their second X chromosome, so
although 1 in 4000 are affected they tend to be more mildly affected than males.)
- Haemophilia: (a defect in the blood clotting system. For example in Haemophilia A an essential clotting
factor, factor VIII, is low or missing. Each condition may be severe, moderate or mild. Haemophilia A and B are X-linked recessive
conditions so women carry the conditions but don't suffer from them because they have a normal copy of the gene on their other
X chromosome. Men with the gene have Haemophilia.
- Duchenne muscular dystrophy: Muscular dystrophies are a group of more than 20 different genetic neuro-muscular
disorders, some more debilitating than others. Most involve mutations in genes involved in muscle structure and function -
in Duchenne MD for example, there is a single genetic fault in the production of a protein in muscle fibres called dystrophin.
- X-linked eye disorders.
- Colour-blindness.
- Hairy ears (one of the few genes carried on the Y chromosome so only men get this facial characteristic).
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A
few examples of disorders in the embryo:
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Autosomal Recessive |
Autosomal
Dominant |
Sex-linked |
Chromosomal
Abnormalities |
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Cystic
Fibrosis |
Huntington’s
Disease |
Hemophilia |
Translocation |
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Tay Sach's Disease |
Congenital
Adrenal Hyperplasia |
Duchenne
Muscular Dystrophy |
Klienfelters
Syndrome |
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Thalassemia |
Marfans
Syndrome |
Fragile
X |
Aneuploidy |
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Sickle
Cell Disease |
Myotonic
Distrophy |
X Linked
Mental Retardation |
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Spinal Muscular Dystrophy
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