疾病背景介紹

骨髓增生異常綜合征(myelodysplastic syndromes, MDS)是起源于造血干細(xì)胞的一組異質(zhì)性髓系克隆性疾病，特點是髓系細(xì)胞分化及發(fā)育異常，表現(xiàn)為無效造血、難治性血細(xì)胞減少、造血功能衰竭，高風(fēng)險向急性髓系白血病（AML）轉(zhuǎn)化。20q染色體缺失的MDS患者的預(yù)后較好，其病情經(jīng)過平穩(wěn)，轉(zhuǎn)白血病率低，中位生存率低。

探針描述

7q探針，主要是以紅色熒光分子標(biāo)記20q12 DNA區(qū)域為探針，約352Kb，使其與骨髓間期細(xì)胞細(xì)胞核內(nèi)的基因序列雜交互補，因此具有極高的特異性。如圖所示

臨床意義

對于具有治療指征的患者根據(jù)FISH結(jié)果分層，選擇不同的治療方案。20q出現(xiàn)缺失見于MPD/MDS（4%）/AML（1%）等疾病中，預(yù)后較好，其中20q12微小區(qū)域缺失見于MPD和MDS中。因此，染色體核型分析對于MDS的診斷和預(yù)后判斷具有重要意義。

參考文獻(xiàn)

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