King Abdullah International Medical Research Centre, Riyadh, Saudi Arabia.
Neurology Department, King Fahd Medical City Hospital, Riyadh, Saudi Arabia.
Mol Genet Genomic Med. 2022 Nov;10(11):e2049. doi: 10.1002/mgg3.2049. Epub 2022 Sep 5.
Spinal Muscular Dystrophy (SMA) is one of the leading causes of death in infants and young children from heritable diseases. Although no large-scale popultion-based studies have been done in Saudi Arabia, it is reported that the incidence of SMA is higher in the Saudi population partly because of the high degree of consanguineous marriages.
The final analysis included 4198 normal volunteers aged between 18 and 25 years old, 54.7% males, and 45.3% females. Whole blood was spotted directly from finger pricks onto IsoCode StixTM and genomic DNA was isolated using one triangle from the machine. To discern the SMN1 copy number independently from SMN2, Multiplex PCR with Dral restriction fragment analysis was completed. We used the carrier frequency and population-level data to estimate the prevalence of SMA in the population using the life-table method.
This data analysis showed the presence of one copy of the SMN1 gene in 108 samples and two copies in 4090 samples, which resulted from a carrier frequency of 2.6%. The carrier frequency was twofold in females reaching 3.7% compared to 1.6% in males. 27% of participants were children of first-cousin marriages. We estimated the birth incidence of SMA to be 32 per 100,000 birth and the total number of people living with SMA in the Kingdom of Saudi Arabia to be 2265 of which 188 are type I, 1213 are type II, and 8,64 are type III.
The SMA carrier rate of 2.6% in Saudi control subjects is slightly higher than the reported global frequency of 1.25 to 2% with links to the high degree of consanguinity.
脊髓性肌萎缩症（SMA）是导致遗传性疾病婴儿和幼儿死亡的主要原因之一。虽然沙特阿拉伯尚未进行大规模的基于人群的研究，但据报道，由于高度近亲结婚，SMA 在沙特人群中的发病率较高。
最终分析包括 4198 名年龄在 18 至 25 岁之间的正常志愿者，其中 54.7%为男性，45.3%为女性。直接从手指刺破处采集全血点样到 IsoCode StixTM 上，使用机器上的一个三角形分离基因组 DNA。为了独立于 SMN2 识别 SMN1 拷贝数，完成了多重 PCR 与 Dral 限制片段分析。我们使用携带者频率和人群水平数据，使用寿命表法估计人群中 SMA 的患病率。
这项数据分析显示，在 108 个样本中存在一个 SMN1 基因拷贝，在 4090 个样本中存在两个拷贝，这导致携带者频率为 2.6%。女性的携带者频率是男性的两倍，达到 3.7%，而男性为 1.6%。27%的参与者是表亲婚姻的子女。我们估计 SMA 的出生发病率为每 100000 例出生 32 例，沙特阿拉伯王国的 SMA 患者总数为 2265 例，其中 188 例为 I 型，1213 例为 II 型，864 例为 III 型。
沙特对照组 SMA 携带者率为 2.6%，略高于全球报道的 1.25%至 2%的频率，与高度近亲结婚有关。
