Carrier frequency of autosomal-recessive disorders in the Ashkenazi Jewish population: should the rationale for mutation choice for screening be reevaluated?
BACKGROUND
Ashkenazi Jewish (AJ) population is at increased risk for several recessive inherited diseases. Therefore, carrier testing of AJ members is important in order to identify couples at risk of having offspring with an autosomal recessive disorder.


METHODS
In the present study, a database containing the results of 28 410 genotyping assays was screened. Ten thousand seventy eight nonselected healthy members of the AJ population were tested for carrier status for the following diseases; Gaucher disease (GD), cystic fibrosis (CF), Familial dysautonomia (FD), Alpha 1 antitrypsin (A1AT), Mucolipidosis type 4 (ML4), Fanconi anemia type C (FAC), Canavan disease (CD), Neimann-Pick type 4 (NP) and Bloom syndrome (BLM).


RESULTS
The results demonstrated that 635 members were carriers of one mutation and 30 members were found to be carriers of two mutations in the different genes related to the development of the above mentioned diseases. GD was found to have the highest carrier frequency (1:17) followed by CF (1:23), FD (1:29), A1AT (1:65), ML4 (1:67) and FAC (1:77). The carrier frequency of CD, NP and BLM was 1:82, 1:103 and 1:157, respectively.


CONCLUSIONS
The frequency of the disease-causing mutations screened routinely among the AJ population indicated that there are rare mutations with very low frequencies. The screening policy of the disease-causing mutations should be reevaluated and mutations with a high frequency should be screened, while rare mutations with a lower frequency may be tested in partners of carriers.
Fares
Fuad
F
Department of Molecular Genetics, Carmel Medical Center, University of Haifa, Haifa 31905, Israel. ffares@sci.haifa.ac.il
Badarneh
Khader
K
Abosaleh
Mohamed
M
Harari-Shaham
Amalia
A
Diukman
Roni
R
David
Miriam
M
D005260:Female; D005808:Genes, Recessive / Q000235:genetics*; D006580:Genetic Carrier Screening; D030342:Genetic Diseases, Inborn / Q000175:diagnosis* / Q000235:genetics*; D005820:Genetic Testing / Q000379:methods; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D007585:Jews / Q000235:genetics*; D008297:Male; D009154:Mutation