MyMedR

Displaying all 4 publications

Abstract:

Sort:

Fulltext Clinical, biochemical and mutational findings in biotinidase deficiency among Malaysian population

Mardhiah M, Azize NAA, Yakob Y, Affandi O, Hock NL, Rowani MR, et al.

Mol Genet Metab Rep, 2020 Mar;22:100548.
PMID: 32300527 DOI: 10.1016/j.ymgmr.2019.100548

Introduction: Biotinidase deficiency (BD) is an autosomal recessively inherited disorder characterized by developmental delay, seizures, hypotonia, ataxia, skin rash/eczema, alopecia, conjunctivitis/visual problem/optic atrophy and metabolic acidosis. Delayed diagnosis may lead to irreversible neurological damage.
Methodology: Clinically suspected patients were screened for biotinidase level by a fluorometry method. Profound BD patients were confirmed by mutation analysis of BTD gene.
Results: 9 patients had biotinidase activity of less than 77 U. 3 patients (33%) had profound BD while 6 patients (67%) had partial BD. Compound heterozygous mutations were detected at c.98_104delinsTCC p.(Cys33Phefs*36) in Exon 2 and c.833T>C p.(Leu278Pro) in Exon 4 in two patients and a homozygous mutation at c.98_104delinsTCC p.(Cys33Phefs*36) in Exon 2 in another patient.
Conclusion: Correct diagnosis lead to early treatment and accurate management of patient. Biochemical screening of BD in symptomatic child is prerequisite to determine enzyme status however molecular confirmation is vital in differentiating individuals with profound biotinidase deficiency from partial biotinidase deficiency and also individuals' carriers.
Carbamoylphosphate synthetase 1 (CPS1) deficiency: clinical, biochemical, and molecular characterization in Malaysian patients

Ali EZ, Khalid MK, Yunus ZM, Yakob Y, Chin CB, Abd Latif K, et al.

Eur J Pediatr, 2016 Mar;175(3):339-46.
PMID: 26440671 DOI: 10.1007/s00431-015-2644-z

Carbamoyl phosphate synthetase 1 (CPS1) deficiency is a rare autosomal recessive disorder of ureagenesis presenting as life-threatening hyperammonemia. In this study, we present the main clinical features and biochemical and molecular data of six Malaysian patients with CPS1 deficiency. All the patients have neonatal-onset symptoms, initially diagnosed as infections before hyperammonemia was recognized. They have typical biochemical findings of hyperglutaminemia, hypocitrullinemia, and low to normal urinary excretion of orotate. One neonate succumbed to the first hyperammonemic decompensation. Five neonatal survivors received long-term treatment consisting of dietary protein restriction and ammonia-scavenging drugs. They have delayed neurocognitive development of varying severity. Genetic analysis revealed eight mutations in CPS1 gene, five of which were not previously reported. Five mutations were missense changes while another three were predicted to create premature stop codons. In silico analyses showed that these new mutations affected different CPS1 enzyme domains and were predicted to interrupt interactions at enzyme active sites, disturb local enzyme conformation, and destabilize assembly of intact enzyme complex.
CONCLUSION: All mutations are private except one mutation; p.Ile1254Phe was found in three unrelated families. Identification of a recurrent p.Ile1254Phe mutation suggests the presence of a common and unique mutation in our population. Our study also expands the mutational spectrum of the CPS1 gene.
Fulltext A systematic review of the prevalence of Morquio A syndrome: challenges for study reporting in rare diseases

Leadley RM, Lang S, Misso K, Bekkering T, Ross J, Akiyama T, et al.

Orphanet J Rare Dis, 2014;9:173.
PMID: 25404155 DOI: 10.1186/s13023-014-0173-x

Morquio A (MPS IVA) is a rare disease characterised by a deficiency of N-acetylgalactosamine-6 sulfatase (GALNS) and presenting with short stature, abnormal gait, cervical spine instability and shortened lifespan.
Mutation spectrum of and founder effects affecting the PTS gene in East Asian populations

Chiu YH, Chang YC, Chang YH, Niu DM, Yang YL, Ye J, et al.

J Hum Genet, 2012 Feb;57(2):145-52.
PMID: 22237589 DOI: 10.1038/jhg.2011.146

The enzyme 6-pyruvoyl-tetrahydropterin synthase (PTPS, gene symbol: PTS) is involved in the second step of the de novo biosynthesis of tetrahydrobiopterin (BH4), which is a vital cofactor of nitric oxide synthases and three types of aromatic amino acid hydroxylases; the latter are important enzymes in the production of neurotransmitters. We conducted a study of PTS mutations in East Asia, including Taiwan, Mainland China, Japan, South Korea, the Philippines, Thailand and Malaysia. A total of 43 mutations were identified, comprising 22 previously reported mutations and 21 new discovered mutations. Among these, the c.155A>G, c.259C>T, c. 272A>G, c.286G>A and c.84-291A>G mutations were the most common PTS mutations in East Asia, while the c.58T>C and c.243G>A mutations were, respectively, specific to Filipinos and Japanese originating from Okinawa. Further studies demonstrated that each of the mutations listed above was in linkage disequilibrium to a specific allele of polymorphic microsatellite marker, D11S1347. These results suggest the presence of founder effects that have affected these frequent mutations in East Asia populations. In this context, D11S1347 should become one of the most reliable polymorphic markers for use in prenatal diagnosis among PTPS deficient families, especially where mutations are yet to be identified.