脊髓性肌肉萎縮症是一種體染色體隱性基因疾病,病患有兩個缺失或突變的SMN1基因,從父親及母親身上各遺傳一個4:

基因檢測是診斷SMA很重要的工具

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建議將SMN1基因缺失試驗作為疑似患有脊髓性肌肉萎縮症患者的第一診斷步驟。

可以經由聚合酶鍊式反應 (PCR) 測定來確定兩個染色體上的SMN1第七外顯子7是否缺失,此缺失在95%的SMA病患中發生。dPCR能夠可靠且準確地測量的SMN1SMN2基因數量(即0-6個拷貝數)。5,9

國健署指定之基因診斷醫療機構

優生保健法:
第二條 本辦法減免或補助費用之優生保健措施如下:
一、遺傳性疾病檢查
(一)經中央主管機關認定之新生兒先天性代謝異常疾病篩檢。
(二)經中央主管機關認定之新生兒先天性代謝異常疾病陽性個案之確認診斷。
(三)海洋性貧血檢查。
(四)血液細胞遺傳學檢驗。
(五)產前遺傳診斷,包括細胞遺傳學檢驗、基因檢驗、生化遺傳學或其他產前遺傳診斷之檢驗。
(六)流產組織或死產者之確認診斷。
(七)其他經中央主管機關認定之遺傳性疾病檢查。
持有效期證明之指定檢驗機構,得依優生保健措施減免或補助費用辦法及罕見疾病醫療照護費用補助辦法之規定,申請受檢者檢驗費用之補助
審查通過之「遺傳性及罕見疾病指定檢驗機構」名單,請參閱以下網站:
https://www.hpa.gov.tw/Pages/Detail.aspx?nodeid=4083&pid=411&sid=407

目前可選擇SMA新生兒篩檢。SMA的診斷時間至關重要。根據疾病的自然病史,早期診斷之後的早期介入可能有助於改善SMA患者的預後。15

References

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診斷過程如何與父母/照護者的觀點不同?

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