Metachromatic Leukodystrophy (MLD) is an autosomal recessive leukodystrophy, characterized by a buildup of sulfatide fat in cells, especially in cells of the nervous system. The sulfatide accumulation stains differently and appears in the form of metachromatic granules under the microscope. The accumulation causes progressive destruction of the myelin sheath, leading to characteristic signs and symptoms. It is estimated that MLD occurs in every one in about 40,000 individuals worldwide. However, some populations, including some Arab groups in Palestine and a group of Jews who migrated from Southern Arabia (Habbanites) have been shown to have much higher frequencies of the disease.