Abstract：
Alagille syndrome (ALGS) is an autosomal dominant, multisystem disorder that typically presents with cholestasis, cardiac, ocular, skeletal, vascular and renal abnormalities, and distinct facial features. Most cases are due to variants in the JAG1 gene, with only a small percentage involving a complete gene deletion.
OBJECTIVE: to contribute to the phenotype delineation and interpretation of a microdeletion not previously described in the literature on chromosome 20.
METHODS: A 4-month-old female patient was diagnosed with a heart murmur. An echocardiogram revealed pulmonary artery stenosis, which, combined with a prominent forehead observed on physical examination, determined her referral to clinical genetics. Because ALGS was suspected, complementary studies were performed, revealing butterfly vertebras and a genetic panel identified a pathogenic heterozygous deletion, encompassing the entire coding sequence of the JAG1 gene. To rule out a more extensive deletion, a chromosome microarray was performed, confirming a pathogenic microdeletion on chromosome 20 of 378 kb (arr[GRCh37] 20p12.2(10414643_10792802)x1).
CONCLUSIONS: A targeted sequencing panel followed by confirmation with a chromosome microarray allowed the identification and delineation of a pathogenic microdeletion not previously reported in the literature, including the complete JAG1 gene in a Chilean patient whose phenotype is consistent with ALGS.
OBJECTIVE: to contribute to the phenotype delineation and interpretation of a microdeletion not previously described in the literature on chromosome 20.
METHODS: A 4-month-old female patient was diagnosed with a heart murmur. An echocardiogram revealed pulmonary artery stenosis, which, combined with a prominent forehead observed on physical examination, determined her referral to clinical genetics. Because ALGS was suspected, complementary studies were performed, revealing butterfly vertebras and a genetic panel identified a pathogenic heterozygous deletion, encompassing the entire coding sequence of the JAG1 gene. To rule out a more extensive deletion, a chromosome microarray was performed, confirming a pathogenic microdeletion on chromosome 20 of 378 kb (arr[GRCh37] 20p12.2(10414643_10792802)x1).
CONCLUSIONS: A targeted sequencing panel followed by confirmation with a chromosome microarray allowed the identification and delineation of a pathogenic microdeletion not previously reported in the literature, including the complete JAG1 gene in a Chilean patient whose phenotype is consistent with ALGS.
摘要：
Alagille综合征(ALGS)是一种常染色体显性,通常表现为胆汁淤积的多系统疾病，心脏,眼,骨骼，血管和肾脏异常，和独特的面部特征。大多数病例是由于JAG1基因的变异，只有一小部分涉及完全基因缺失。
目的：有助于对以前在20号染色体文献中没有描述的微缺失进行表型描述和解释。
方法：一名4个月大的女性患者被诊断为心脏杂音。超声心动图显示肺动脉狭窄,which,结合在体检中观察到的突出的前额，决定她转诊到临床遗传学。因为ALGS被怀疑,进行了补充研究，揭示蝴蝶椎骨和遗传小组鉴定出致病性杂合缺失，包含JAG1基因的整个编码序列。为了排除更广泛的删除，进行了染色体微阵列，确认378kb的20号染色体上的致病性微缺失（ARr[GRCh37]20p12.2（10414643_10792802）x1）。
结论：靶向测序小组，然后用染色体微阵列进行确认，可以鉴定和描绘以前文献中未报道的致病性微缺失，包括一名智利患者的完整JAG1基因，其表型与ALGS一致。
目的：有助于对以前在20号染色体文献中没有描述的微缺失进行表型描述和解释。
方法：一名4个月大的女性患者被诊断为心脏杂音。超声心动图显示肺动脉狭窄,which,结合在体检中观察到的突出的前额，决定她转诊到临床遗传学。因为ALGS被怀疑,进行了补充研究，揭示蝴蝶椎骨和遗传小组鉴定出致病性杂合缺失，包含JAG1基因的整个编码序列。为了排除更广泛的删除，进行了染色体微阵列，确认378kb的20号染色体上的致病性微缺失（ARr[GRCh37]20p12.2（10414643_10792802）x1）。
结论：靶向测序小组，然后用染色体微阵列进行确认，可以鉴定和描绘以前文献中未报道的致病性微缺失，包括一名智利患者的完整JAG1基因，其表型与ALGS一致。
