Variation Resources
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User Question 5: Identify disease-causing mutations
  Sample User Question
Flow Chart
Step By Step Guide
  

Sample User Question back to top

What disorders are caused by a mutation to the gene HFE? Do all known substitutions in this gene cause disease? How many SNPs have been located in the HFE gene?

Flow Chart back to top

  1. OMIM - Search OMIM to find gene and genetic disorder records based on particular criteria. Check list of allelic variants to determine disorders and non-disorder variation
    Down Arrow
  2. dbSNP - Link to dbSNP to see actual SNP records for the genetic disorders
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  3. Entrez Gene - Link to "Entrez Gene" to get links to dbSNP for all SNPs present in the gene and to "GeneView in dbSNP" for finding the locations of all SNPs on the gene

Step By Step Guide back to top

OMIM
  • Limit search to title; type in HFE and click "go"
  • Click "*235200" to retrieve the record for Hereditary Hemochromatosis (HFE Gene included).
  • Click on "View List" under "Allelic Variants".
  • Note that two disorders are listed: Hemochromatosis and Porphyria Variegata
  • Note that three other variants are listed as "polymorphisms": .004-.006.
  • Click on these links to see if any clinical sympotoms are listed (none are; from these records, the three polymorphisms appear not to cause disease. Check the papers cited to be sure).
dbSNP
  • Click on the "SNP" link in OMIM.
  • Three reference SNP clusters are retrieved; one (rs1799945) of which has been mapped to Chromosome 6.
  • Click on the hyperlinked "rs1799945" to retrieve the reference SNP record.
Entrez Gene
  • To find additional SNPs in the area of HFE, link to Gene for the "HFE" locus.
  • Click on "SNP" to retrieve all ref SNP records for HFE gene.
  • Click on "GeneView in dbSNP" to view the locations of SNPs in the HFE gene


Genetic Variation Return to Slides (*.html or *.mht format -- slide 103)
Return to Exercises List		 Revised 07/24/2007