Is there any relationship between mutation in CPS1 Gene and pregnancy loss?

Abstract

Background: Carbamoyl phosphate synthetase 1 (CPS1) is a liver-specific enzyme with the lowest enzymatic rate, which determines the overall rate of the other reactions in the pathway that converts ammonia to carbamoyl phosphate in the first step of the urea cycle. Carbamoyl phosphate synthetase 1 deficiency (CPS1D), which usually presents as lethal hyperammonemia, is a rare autosomal recessive hereditary disease.


Case: We report a case of a two-day-old female neonate with lethal hyperammonemia. The newborn infant was presented with hyperammonemia (34.7 μg/ml; reference range 1.1–1.9). In Plasma amino acid analysis, there was a significant elevated levels of alanine (3,004 μmol/L; reference range, 236–410 μmol/L), glutamine (2,256 μmol/L; reference range, 20–107 μmol/L), asparagine (126 μmol/L; reference range, 30–69 μmol/L), glutamic acid (356 μmol/L; reference range, 14–192 μmol/L), aspartic acid (123 μmol/L; reference range, 0–24 μmol/L), and lysine (342 μmol/L; reference range, 114–269 μmol/L). We cannot diagnose the urea cycle disorder (UCD) CPS1D properly only based on the quantity of biochemical intermediary metabolites to exclude other UCDs with similar symptoms. Following next generation sequencing determined one homozygous mutation in CPS1 gene and also this mutation was determined in her parents. The identified mutation was c.2758G > C; p.Asp920His, in the 23 exon of CPS1. This novel homozygous mutation had not been reported previously.


Conclusion: We applied whole exome sequencing successfully to diagnose the patient with CPS1D in a clinical setting. This result supports the clinical applicability of whole exome sequencing for cost-effective molecular diagnosis of UCDs.

References
[1] Morris SM Jr. Regulation of enzymes of urea and arginine synthesis. Ann Rev Nutr 1992; 12: 81–101.

[2] Diez-Fernandez C, Häberle J. Targeting CPS1 in the treatment of Carbamoyl phosphate synthetase 1 (CPS1)
deficiency, a urea cycle disorder. Exp Opin Ther Targets 2017; 21: 391–399.

[3] Mian A, Lee B. Urea-cycle disorders as a paradigm for inborn errors of hepatocyte metabolism. Trends Mol Med 2002; 8: 583–589.

[4] Lee B. Urea cycle disorders: Management. UpToDate, Waltham, MA Wolters Kluwer Health. 2017.

[5] Butler SL, Dong H, Cardona D, Jia M, Zheng R, Zhu H, et al. The antigen for Hep Par 1 antibody is the urea cycle enzyme carbamoyl phosphate synthetase 1. Lab Invest 2008; 88: 78–88.

[6] Keskinen P, Siitonen A, Salo M. Hereditary urea cycle diseases in Finland. Acta Paediatr 2008; 97: 1412–1419.

[7] Nagata N, Matsuda I, Oyanagi K. Estimated frequency of urea cycle enzymopathies in Japan. Am J Med Genet 1991; 39: 228–229.

[8] Kurokawa K, Yorifuji T, Kawai M, Momoi T, Nagasaka H, Takayanagi M, et al. Molecular and clinical analyses of
Japanese patients with carbamoylphosphate synthetase1 (CPS1) deficiency. J Hum Genet 2007; 52: 349–354.

[9] Díez-Fernández C, Hu L, Cervera J, Häberle J, Rubio V. Understanding carbamoyl phosphate synthetase (CPS1)
deficiency by using the recombinantly purified human enzyme: effects of CPS1 mutations that concentrate in a
central domain of unknown function. Mol Genet Metab 2014; 112: 123–132.

[10] Choi R, Park HD, Yang M, Ki CS, Lee SY, Kim JW, et al. Novel pathogenic variant (c. 580C> T) in the CPS1 gene
in a newborn with carbamoyl phosphate synthetase 1 deficiency identified by whole exome sequencing. Ann
Lab Med 2017; 37: 58–62.

[11] Kutteh WH, Jaslow CR, Ke RW. Elevated homocysteine levels in women with recurrent pregnancy loss (RPL) are associated with A1298C mutations of methylenetetrahydrofolate reductase (MTHFR) in the absence of C677T
mutations. Fertil Steril 2006; 86: S472–S473.

[12] Lange LA, Croteau-Chonka DC, Marvelle AF, Qin L, Gaulton KJ, Kuzawa CW, et al. Genome-wide association
study of homocysteine levels in Filipinos provides evidence for CPS1 in women and a stronger MTHFR effect
in young adults. Hum Mol Genet 2010; 19: 2050–2058.

[13] Van Spronsen F, Smit G, Erwich J. Inherited metabolic diseases and pregnancy. Int J Obstet Gynaecol 2005; 112:2–11.

[14] Srinivasan RC, Zabulica M, Hammarstedt C, Wu T, Gramignoli R, Kannisto K, et al. A liver-humanized mouse
model of carbamoyl phosphate synthetase 1-deficiency. J Inherit Metab Dis 2019: 1–10.

[15] Funghini S, Thusberg J, Spada M, Gasperini S, Parini R, Ventura L, et al. Carbamoyl phosphate synthetase
1 deficiency in Italy: clinical and genetic findings in a heterogeneous cohort. Gene 2012; 493: 228–234.

[16] Lee J, Yang A, Kim J, Park H-D, Lee S, Lee S-K, et al. A Case of Carbamoyl Phosphate Synthetase 1 Deficiency
with Novel Mutations in CPS1 Treated by Liver Cell Transplantation. J Korean Soc Inherited Metabol Dis 2017;
17: 31–37.

[17] Burgard P, Kölker S, Haege G, Lindner M, Hoffmann GF. Neonatal mortality and outcome at the end of the first year of life in early onset urea cycle disorders-review and metaanalysis of observational studies published over more than 35 years. J Inherit Metab Dis 2016; 39: 219–229.

[18] McMillan HJ, Telegrafi A, Singleton A, Cho MT, Lelli D, Lynn FC, et al. Recessive mutations in ATP8A2 cause severe hypotonia, cognitive impairment, hyperkinetic movement disorders and progressive optic atrophy. Orphanet J Rare dis 2018; 13: 86.