Prenatal diagnosis and genetic counselling for a pedigree carrying a large fragment deletion of 13q / 中华医学遗传学杂志

OBJECTIVE@#To carry out prenatal diagnosis for a fetus with normal ultrasonographic finding at 20 weeks' gestation but a copy number variant(CNV) of 13q indicated by non-invasive prenatal test (NIPT).@*METHODS@#Karyotyping analysis and chromosomal CNV assay were carried out on the amniotic fluid sample. Parental peripheral blood sample was collected for chromosomal analysis. Detailed fetal ultrasound scan was carried out to rule out structural abnormalities of the fetus.@*RESULTS@#The fetus was detected with a heterozygous 10.14 Mb deletion at 13q21.1q21.32, which has originated from the phenotypically normal mother. No apparent karyotypic abnormality was detected in the fetus and its parents. No ultrasonic abnormality was found in the fetus.@*CONCLUSION@#Both the fetus and its mother have carried a heterozygous 10.14 Mb deletion at 13q21.1q21.32 and presented normal phenotypes.Combined with literature review, the segmental deletion was judged to be a benign variant.

Clinical phenotype and genetic analysis of three pedigrees with 17q12 microdeletion syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic etiology of three pedigrees with a gestational history of fetal renal anomalies.@*METHODS@#Peripheral venous blood or skin samples were derived from the probands of the three pedigrees. Copy number variation sequencing (CNV-seq) was applied to detect alterations of genome CNVs.@*RESULTS@#The patient from pedigree 1 and the fetuses from pedigrees 2 and 3 all carried a heterozygous 17q12 deletion, with the size ranging from 1.4 Mb to 1.48 Mb encompassing the HNF1B gene.@*CONCLUSION@#The diagnosis of 17q12 microdeletion may be difficult during fetal period for its variable phenotypes. Alterations of chromosomal copy numbers need to be excluded in such patients.

Ultrasonographic manifestation and genetic analysis of a fetus with nephronophthisis type 2 / 中华医学遗传学杂志

OBJECTIVE@#To carry out genetic analysis for a family with a fetus manifesting bilateral polycystic renal dysplasia and oligohydramnios at 16 gestational week and a previous history for fetal renal anomaly.@*METHODS@#Ultrasound scan was carried out to detect the morphological changes. Following genetic counselling, the parents had decided to terminate the pregnancy. Fetal kidneys were subjected to histological examination. Target capture and next generation sequencing (NGS) was applied to the abortus to detect potential variants. The results were verified by Sanger sequencing.@*RESULTS@#Histological examination of fetal kidneys revealed cystic changes without cortex, medulla or normal renal structure. NGS has identified a heterozygous c.100+1G>A variant and deletion of exon 3 of the INVS gene, which were respectively inherited from the mother and father.@*CONCLUSION@#Through NGS and Sanger sequencing, the fetus was diagnosed with type II nephronophthisis (NPHP2). Above result can provide guidance for further pregnancy and enforce understanding of clinical features and genetic etiologies for NPHP.

Phenotype and genetic analysis of a pedigree affected with progressive familial intrahepatic cholestasis / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic etiology for a pedigree affected with progressive familial intrahepatic cholestasis (PFIC).@*METHODS@#Target sequence capture and next generation sequencing (NGS) were applied for the proband. PCR and Sanger sequencing were used to verify the suspected mutation in his sister with similar symptoms and his parents.@*RESULTS@#The proband and his sister manifested after birth with symptoms including jaundice, pruritus and developmental retardation. NGS has identified compound heterozygous mutations of ABCB11 gene, which encodes bile salt export pump protein (BSEP), namely c.2494C>T (p.Arg832Cys) and c.3223C>T (p.Gln1075*), in the proband, which were inherited from his father and mother respectively. His sister carried the same compound mutations.@*CONCLUSION@#Based on the phenotype and genetic testing, the patients were diagnosed as PFIC2 caused by mutation of the ABCB11 gene. The c.3223C>T is a novel nonsense mutation which may cause premature termination of translation. Above results have enriched the spectrum of ABCB11 mutations and provided new evidence for the molecular basis of PFIC, which also facilitated genetic counseling for this pedigree.

Phenotype and genetic analysis of three patients with PKHD1 associated autosomal recessive polycystic kidney disease at childhood, teenage and advanced age / 中华医学遗传学杂志

Objective@#The phenotype and genetics of three patients with autosomal recessive polycystic kidney disease (ARPKD) at childhood, teenage and advanced age were analyzed.@*Methods@#Next generation sequencing (NGS) was applied to all the probands. PCR and Sanger sequencing were used to verify the suspicious gene variants screened by NGS in the probands and their family members, and one of the family got prenatal diagnosis.@*Results@#Through NGS, PCR and Sanger sequencing, the 5-yr proband in pedigree 1 was shown to carry compound heterozygous variants of c. 5935G>A(p.G1979R) and c. 5428G>T(p.E1810X) of PKHD1, originated from his parents; In pedigree 2, the 17-ys proband was detected with c. 5512T>C(p.Y1838H) and c. 5935G>A(p.G1979R) variants of PKHD1 orginated from her parents, and her mother also got prenatal diagnosis during the second trimester; In pedigree 3, the 70-ys female proband was found with variants c. 11314C>T (p.R3772X) and c. 3860T>G (p.V1287G) of PKHD1.@*Conclusion@#The three pedigrees were diagnosed as ARPKD caused by PKHD1 variants. Five types of variants were detected, c. 5935G>A and c. 11314C>T were the known pathogenic variants, while c. 5512T>C, c. 5428G>T and c. 3860T>G were not reported previously. Considering the complexity of the genetics and phenotypes of the cystic renal diseases, genetic diagnosis is crucial to give accurate etiological diagnosis, which may benefit the clinic management.

Preparation of antibody against ANKRD22 and its expression in colorectal cancer / 预防医学

Objective@# To prepare the monoclonal antibody against ankyrin repeat domain 22（ANKRD22）and to investigate its expression in colorectal cancer tissues.@*Methods @#The recombinant human ANKRD22 was expressed through E. coli and pET-42a and then used to immunize Balb/c mice after purification. Anti-human ANKRD22 specific monoclonal antibodies were selected by Western blotting with 293T cell lysate highly expressing ANKRD22 as antigen. The expression of ANKRD22 in the tissue microarrays of 112 patients with colorectal cancer was detected by immunohistochemical staining.@*Results @#Four specific monoclonal antibodies against human ANKRD22 were screened out of 93 hybridoma cells,which reacted well with natural human ANKRD22. ANKRD22 was mainly distributed in the cytoplasm of colorectal cancer cells. In 112 cases of colorectal cancer,94 cases were detected positive for ANKRD22 expression,with the positive rate of 83.93%. The expression of ANKRD22 was statistically correlated with the expression of p53 and β-catenin（P<0.05）,but not with age,sex,location of tumors,AJCC stage,Dukes stage,degree of differentiation,lymph node metastasis and mismatch repair gene expression（P>0.05）.@*Conclusion @#The expression level of ANKRD22 was high in colorectal cancer. ANKRD22 might be involved in the carcinogenesis of colorectal epithelium and be a potential diagnostic marker.

Phenotype and genetic analysis of three patients with PKHD1 associated autosomal recessive polycystic kidney disease at childhood, teenage and advanced age / 中华医学遗传学杂志

OBJECTIVE@#The phenotype and genetics of three patients with autosomal recessive polycystic kidney disease (ARPKD) at childhood, teenage and advanced age were analyzed.@*METHODS@#Next generation sequencing (NGS) was applied to all the probands. PCR and Sanger sequencing were used to verify the suspicious gene variants screened by NGS in the probands and their family members, and one of the family got prenatal diagnosis.@*RESULTS@#Through NGS, PCR and Sanger sequencing, the 5-yr proband in pedigree 1 was shown to carry compound heterozygous variants of c.5935G>A(p.G1979R) and c.5428G>T(p.E1810X) of PKHD1, originated from his parents; In pedigree 2, the 17-ys proband was detected with c.5512T>C(p.Y1838H) and c.5935G>A(p.G1979R) variants of PKHD1 orginated from her parents, and her mother also got prenatal diagnosis during the second trimester; In pedigree 3, the 70-ys female proband was found with variants c.11314C>T (p.R3772X) and c.3860T>G (p.V1287G) of PKHD1.@*CONCLUSION@#The three pedigrees were diagnosed as ARPKD caused by PKHD1 variants. Five types of variants were detected, c.5935G>A and c.11314C>T were the known pathogenic variants, while c.5512T>C, c.5428G>T and c.3860T>G were not reported previously. Considering the complexity of the genetics and phenotypes of the cystic renal diseases, genetic diagnosis is crucial to give accurate etiological diagnosis, which may benefit the clinic management.