safeT21 is a non-invasive prenatal DNA test developed for the screening of fetal chromosomal abnormalities, such as Down syndrome (唐氏), Edwards syndrome (trisomy 18) (愛德華氏症患者經常伴隨肢體障礙、畸形及智能障礙等問題,一般出生後即會出現症狀,且終身無法治癒) and Patau syndrome (trisomy 13). (巴陶氏症候群(Patau syndrome),又稱13-三體症,染色體三倍體症之一,少見,患者多在出生後一年內死亡)