建立台灣人之D17S9A、D17S9B 及D17S4A短片段重複序列頻率並以此快速診斷恰克-馬利-杜斯氏症及遺傳性壓力易感性神經病變

Establishment of Allele Frequency of Three Short Tandem Repeats, D17S9A, D17S9B and D17S4A in Taiwanese and Their Clinical Application for Rapid Diagnosis of CMT1A and HNPP

王美嘉(Mei-Chia Wang) ； 羅榮昇(Long-Sun Ro) ； 陳定平(Ding-Ping Chen) ； 張璧月(Pi-Yueh Chang) ； 吳竹蘭(Chu-Lan Wu) ； 盧章智(Jang-Jih Lu)

《Journal of Biomedical & Laboratory Sciences》 25卷1期 (2013/03) Pp. 30-37

摘要

造成兩種常見的體顯性遺傳性周邊神經病變：恰克-馬利-杜斯氏症（Charcot-Marie-Tooth Disease; CMT）及遺傳性壓力易感性神經病變（Hereditary Neuropathy with Liability to Pressure Palsies; HNPP）的原因，大多與17p11.2-12上1.5Mb DNA片段發生重複或缺損相關，所以必須正確定量基因拷貝數。過去使用RFLP及南方墨點法來分析，但需要大量DNA且耗時，因此我們將發生重複或缺損的DNA片段附近的三對引子（包括D17S9A、D17S9B及D17S4A），設計了多重短片段重複PCR，若在這些位點中出現3個等位基因（allele），或僅出現兩個等位基因，但兩者高度有1倍的差異時，表示該片段基因有重複現象，可判讀為CMT1A；若這些位點只出現1個等位基因，必須考慮是同型合子（homozygous），因此需配合臨床症狀，才可判斷HNPP與否。我們共分析25個出現遺傳性週邊神經病變症狀的案例，結果其中19個為CMT1A、6個為HNPP，由於這些病人均有臨床表徵，因此實驗的敏感度為100%；此外，我們也收集到102位對照組檢體，他們並無週邊神經病變症狀及相關家族史，但有3支在這些位點均出現同型合子，故本檢測法的專一性為97%。我們同時也用對照組，建立台灣D17S9A、D17S9B及D17S4A位點頻率（frequency）資料，此為這三個位點頻率的首度報導。綜上，此方法可快速提供診斷需要，但仍配合臨床醫師診斷，或增加更多位點，以增加結果之鑑別力。

關鍵字

恰克-馬利-杜斯氏症 ； 遺傳性壓力易感性神經病變 ； 台灣人的頻率

並列摘要

Because two common autosomal dominate genetically peripheral neuropathies- Charcot-Marie-Tooth Disease (CMT) and Hereditary Neuropathy with Liability to Pressure Palsies (HNPP) are associated with 1.5Mb DNA duplication or deletion on chromosome 17p11.2-12, accuracy quantification of this gene copy number is very important. RFLP (Restriction fragment length polymorphism) and southern blotting were used to detect CMT1A and HNPP before, but they required large DNA and are time consuming. Consequently, the methods are not facility in clinical laboratory. In this study, three STR loci (D17S9A, D17S9B and D17S4A) closing to this region were used. We designed a multiplex STR PCR to detect gene amount of this area. If the results reveal 3 alleles or two alleles with two times difference of peak high, it indicated that gene duplication; if the results are only one peak, it may be caused by homozygous. Twenty-five patients with peripheral neuropathies were collected in this research, our results shown that 19 patients are CMT1A and 6 patients are HNPP. This indicated the sensitivity of this test is 100% according to the result of this method exact matching to their clinical features. On the other hand, 102 control samples without symptoms or family history about peripheral neuropathies were collected from paternity tests. Three control samples revealed homozygous data in D17S9A, D17S9B and D17S4A STR loci, so that the specificity is 97%. By the way, we set up the frequency data about D17S9A, D17D9B and D17S4A STR loci in Taiwan according to the data from control samples. In conclusion, the 3 STR PCR could serve rapid clinical diagnosis cooperated with doctor's diagnosis or increased STR loci to prevent false diagnosis.

並列關鍵字

Charcot-Marie-Tooth Disease (CMT) ； Hereditary Neuropathy with Liability to Pressure Palsies (HNPP) ； frequency of Taiwan population