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Some SCID Learning Resources

3.  X-linked SCID

From the "Contact a Family" site at inherita.html

X-Linked Disorders: Males are at risk

One normal copy (green x) of a gene on the X chromosome is generally sufficient for normal function. Women who have a defective gene (red x) on one of their two X chromosomes are protected by the normal copy of the same gene on the second chromosome. But men lack this protection, since they have one X and one Y chromosome. Each male child of a mother who carries the defect has a 50 percent risk of inheriting the faulty gene and the disorder. Each female child has a 50 percent chance of being a carrier like her mother.


For data on mutations involving each of the 8 exons, go to:

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4. Autosomal SCID
Back to:
1. ADA-Deficiency SCID
2. PNP-Deficiency SCID
3. X-linked SCID