OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with N-acetylglutamate synthase deficiency. METHODS: Trio whole exome sequencing (WES) was carried out for the pedigree. Pathogenicity of the identified variant was predicted based on the latest recommendation of the American College of Medical Genetics and Genomics (ACMG). Prenatal diagnosis was provided for subsequent pregnancy through Sanger sequencing. RESULTS: Trio WES showed that the proband has carried compound heterozygous c.68delG and c.796G>C variants of NAGS gene, for which the mother and father were respectively heterozygous carriers. Neither variant was reported previously. Based on the ACMG guidelines, the c.68delG variant was classified as "likely pathogenic" (PVS1+PM2), while the c.796G>C variant was classified as with "uncertain significance" (PM2+BP4). Sanger sequencing validated the above findings, and only detected the heterozygous c.796G>C variant in the amniotic fluid sample. The fetus was followed up till 6 month after birth with no obvious abnormality. CONCLUSION The compound heterozygous c.68delG and c.796G>C variants of the NAGS gene probably underlay the disorder in this pedigree, and the resulth asenabled genetic counseling and prenatal diagnosis for this pedigree.
Amino-Acid N-Acetyltransferase/genetics* ; China ; Female ; Genetic Testing ; Humans ; Male ; Mutation/genetics* ; Pedigree ; Pregnancy ; Prenatal Diagnosis ; Urea Cycle Disorders, Inborn/genetics* ; Whole Exome Sequencing

Human arrest defective 1 (hARD1) is an acetyltransferase; its physiological significance remains unclear. To explore the relationship between ARD1 protein and tumors, we detected the hARD1 protein in tumor tissues in vivo. We cloned hARD1 gene from Hela cell and construct recombinant plasmid pET28b-hARD1. The recombinant plasmid was transformed into E. coli BL21 (DE3)plysS. hARD1 protein was expressed by inducing with IPTG(1 mmol/L) and purified up to 95% through Ni2+ chelation affinity chromatography. We used the purified hARD1 protein as antigen immunized the Balb/c mice and obtained the hARD1 specific polyclonal antiserum. Through immunohistochemical analysis of different tumor tissues in vivo, we found that hARD1 expressed at high frequency in breast cancer, prostate cancer and lung cancer, especially, hARD1 expression frequency in breast cancer was up to 70%, which is higher than in the other tumors. These results indicate that the high expression level of hARD1 could be an indicator of the breast cancer. This new finding would be a foundation to further explore the relationship between breast tumor and hARD1.
Acetyltransferases ; analysis ; genetics ; immunology ; Amino Acid Sequence ; Animals ; Antibodies ; blood ; immunology ; Base Sequence ; Biomarkers, Tumor ; Breast Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Female ; Humans ; Immune Sera ; biosynthesis ; Immunization ; Immunohistochemistry ; Lung Neoplasms ; metabolism ; pathology ; Male ; Mice ; Mice, Inbred BALB C ; Molecular Sequence Data ; N-Terminal Acetyltransferase A ; N-Terminal Acetyltransferase E ; Prostatic Neoplasms ; metabolism ; pathology ; Recombinant Proteins ; biosynthesis ; genetics ; immunology