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Cytogenetics |
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| Introduction | ||
| What is a chromosome? | ||
| Human Karyotypes/Spreads | ||
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Cytogenetic Abnormalities |
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| Constitutional | ||
| Aquired | ||
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Mammal Examples |
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| Mouse Karyotype | ||
| Mouse Idiogram | ||
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Methods of chromosome visualization |
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| Banding Patterns | ||
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Fluorescence In-Situ Hybridization (FISH) |
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| FISH Examples | ||
| FISH Cartoon | ||
DiGeorge Syndrome | |
Individuals with the DiGeorge syndrome often have cardiac
defects, immune system deficiencies and can be moderately retarded.
The cause of the DiGeorge syndrome is a defect in chromosome 22, where
one of the bands in the long arm has been deleted. The deletion can be
suspected by looking at the karyotype and can be confirmed by FISH. | |
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| This image shows the karytype of an individual with the DiGeorge syndrome.
By looking carefully at the pair of 22's, you can see that there is a light
band missing in the chromosome to the right. It might be easier to see the
defect in the composite karyotype of chromosome 22 from the same individual. | |
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| This image shows a FISH, where the probe has been used to locate the defect associated with the Digeorge syndrome. Back to Constitutional Cytogenetic Abnormalities | |