Herska M, Moscovich D G, Kalian M, Gottlieb D, Bach G
Am J Med Genet. 1987 Mar;26(3):629-35. doi: 10.1002/ajmg.1320260318.
Two hundred ninety-five psychiatric and neurologic patients were randomly screened for aryl sulfatase A (ASA) activity in lymphocyte extracts. Two of these patients showed very low ASA activity, in the range of metachromatic leukodystrophy (MLD)-affected patients. The residual activity in these low ASA patients showed normal enzyme behavior with regard to ASA kinetic features and the ability to catabolize 14C labeled sulfatide by intact fibroblasts. Taking into account that approximately 3% of the general population are homozygous for the pseudo-aryl sulfatase A gene and are clinically unaffected, the data obtained here indicate that the patients studied in this work, as well as most psychiatric patients reported in the literature with low ASA activity, represent the normal ASA polymorphism. Thus, the very low ASA activity patients are in fact homozygous for the pseudo-deficient allele, which does not result in clinical abnormalities. The clinical symptoms in these psychiatric patients and probably other "variant" MLD patients are therefore not related to low ASA activity.
对295名精神病和神经病患者的淋巴细胞提取物中的芳基硫酸酯酶A（ASA）活性进行了随机筛查。其中两名患者的ASA活性非常低，处于异染性脑白质营养不良（MLD）患者的范围内。这些低ASA活性患者的残余活性在ASA动力学特征以及完整成纤维细胞分解代谢14C标记硫脂的能力方面表现出正常的酶行为。考虑到普通人群中约3%的人是假芳基硫酸酯酶A基因的纯合子且临床上未受影响，此处获得的数据表明，本研究中的患者以及文献中报道的大多数ASA活性低的精神病患者代表正常的ASA多态性。因此，ASA活性极低的患者实际上是假缺陷等位基因的纯合子，这不会导致临床异常。因此，这些精神病患者以及可能其他“变异型”MLD患者的临床症状与低ASA活性无关。
