Jedrzejowska Maria, Milewski Michał, Zimowski Janusz, Borkowska Janina, Kostera-Pruszczyk Anna, Sielska Danuta, Jurek Marta, Hausmanowa-Petrusewicz Irena
Neuromuscular Unit, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warszawa, Poland.
Acta Biochim Pol. 2009;56(1):103-8. Epub 2009 Mar 14.
Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder caused by mutations of the SMN1 gene. It is characterized by significant phenotype variability. In this study, we analyzed possible phenotype modifiers of the disease - the size of the deletion in the SMA region, the number of SMN2 gene copies, as well as the effect of gender. Among the factors analyzed, two seem to influence the SMA phenotype: the number of SMN2 gene copies and a deletion in the NAIP gene. A higher number of SMN2 copies makes the clinical symptoms more benign, and the NAIP gene deletion is associated with a more severe phenotype. The influence of gender remains unclear. In a group of 1039 patients, 55% of whom were male, the greatest disproportion was in the SMA1 (F/M = 0.78) and SMA3b (F/M = 0.45) forms. In SMA1 a deletion in the NAIP gene was seen twice as frequently in girls compared to boys. In three patients, we observed genotypes atypical for the chronic forms of SMA: two patients with SMA3a and 3b had a deletion of the NAIP gene, and a third patient with SMA2 had one copy of the SMN2 gene.
脊髓性肌萎缩症（SMA）是一种由SMN1基因突变引起的常染色体隐性神经肌肉疾病。其特征为显著的表型变异性。在本研究中，我们分析了该疾病可能的表型修饰因子——SMA区域缺失的大小、SMN2基因拷贝数以及性别的影响。在所分析的因素中，有两个因素似乎会影响SMA表型：SMN2基因拷贝数以及NAIP基因的缺失。SMN2拷贝数越多，临床症状越轻，而NAIP基因缺失与更严重的表型相关。性别的影响尚不清楚。在一组1039名患者中，其中55%为男性，最大的性别差异存在于SMA1型（女/男 = 0.78）和SMA3b型（女/男 = 0.45）。在SMA1型中，女孩中NAIP基因缺失的发生率是男孩的两倍。在三名患者中，我们观察到了慢性SMA形式的非典型基因型：两名SMA3a和3b型患者存在NAIP基因缺失，第三名SMA2型患者有一个SMN2基因拷贝。
