To the Editor:
Canavan disease (CD) is an autosomal recessive neurodegenerative disorder affecting white matter and leading to spongy degeneration. Macroencephaly is characteristic in children with this severe leukodystrophy. The disease is caused by the deficiency of aspartoacylase (ASPA) and increased levels of N-acetylaspartic acid (NAA) in brain [Matalon et al., 1988]. Canavan disease is prevalent among Ashkenazi Jews with two predominant mutations C693A and A854C found in 98% of the Jewish cases [Kaul et al., 1993[Kaul et al., , 1994;;Matalon et al., 1993;Matalon, 1997]. The carrier frequency found in a sample of over 4,000 Ashkenazim was 1/37 [Matalon, 1997]. Canavan disease occurs less frequently among non-Jewish populations, and the carrier frequency has not been established. The mutations among the non-Jewish patients are different and more diverse; the most common mutation is C914A observed in 35.7% [Kaul et al., 1994]. Shaag et al. [1995] also found the C914A is the most prevalent mutation among non-Jewish European individuals. Other mutations in non-Jewish patients can randomly reside in exons 1-6, however a higher prevalence of mutations has been detected in exons [3][4][5][6]