New Genetic information

1
New Genetic information !

• Meg Hefner, genetic councelor, Clinical Assistant
  Professor of Pediatrics, St. Louis University
  School of Medicine, reports the new information
  during the Toronto workshop, CHARGE Syndrome
  Parents as Partners in October, 2004
• GENETICS OF CHARGE SYNDROME dominant gene
• August, 2004, the first major CHARGE gene was
  reported. CHD7 is a gene on chromosome 8q12.

2

• Mutations in this gene were identified in about
  65 of children tested, but in none of the
  parents. This confirms CHARGE as an autosomal
  dominant condition, with most cases representing
  new mutations.

3
Should my child be tested?

• Testing is available in the Netharlands
• Cost is 800 US
• All samples which were collected during the
  conference in Houston for the Baylor study are
  being tested now for this gene
• The method used at Baylor is not as labour
  intensive as what is being done in the
  Netharlands
• Success rate for finding the gene in the Baylor
  samples are lower

4
What is the cause of the gene change?

• Presently they do not know what the cause is for
  the change in the gene
• Again, the gene has not been found in parents
• They do know that statistically that the age of
  the father is slightly older then the norm

5

• If my child doesnt have the gene does that mean
  he does not have CHARGE syndrome?
• NO! There are children who are diagnosed with
  CHARGE syndrome who did not have the gene
• There most likely are several genes which could
  cause CHARGE syndrome

6
Other statistics ?

•  
• Prevalence at least 112,000 births although
  highly suspected to be under reported
• Empiric risk of recurrence is 1-2. Risk to
  children of individuals with CHARGE may be 50.
•  There may be mild forms of this syndrome.

7
References

• Hefner, Meg. CHARGE Syndrome Parents as
  Partners workshop, October 2004, Toronto.
• Vissers LELM et al. Mutaitons in a new member of
  the chromodomain gene family cause CHARGE
  syndrome. Nature Genetics online 8/8/04.