No abstract available.
Metabolism, Inborn Errors*

No abstract available.
Korea* ; Metabolism, Inborn Errors*

No abstract available.
Infant, Newborn ; Metabolism, Inborn Errors* ; Neonatal Screening*

Background. X-linked adrenoleukodystrophy (X-ALD) is a progressive genetic disorder affecting the metabolism of very long chain fatty acids in the adrenal glands, spinal cord and white matter of the nervous system. It is an inherited metabolic storage disease whereby a defect in a specific enzyme results in the accumulation of very long-chain fatty acids (VLCFA) that are harmful to some cells and organs. VLCFA analysis for confirmation of X-linked adrenoleukodystrophy is one of the most requested tests among the send-out laboratory services of the Biochemical Genetics Laboratory at the Institute of Human Genetics. This paper aims to review the clinical characteristics and the results of the VLCFA analysis of the patients whose samples we received for testing.Methods. Overseas tests samples received by the Biochemical Genetics Laboratory for VLCFA from 2002-2016 were included. The details of the patients were collated in an overseas tests database and was the main source of the data for this study. The results of the VLCFA tests sent to the Kennedy Krieger Institute and The Children’s Hospital at Westmead were inputted into the said database. Descriptive statistics was utilized in order to examine the clinical and biochemical data of the patients.Results. The results showed that out of the 54 samples submitted to our laboratory, 19 (35%) of the samples received from male patients suspected to have X-ALD yielded positive results and another 10 (19%) females were found to be carriers. Visual defect followed by deteriorating mental status were the most frequent indications for VLCFA testing. Conclusion. Having a significant diagnostic yield of 54%, early diagnosis of X-linked adrenoleukodystrophy in our population is important so that proper management that could prevent the progression of the disease could be timely instituted.
Metabolism, Inborn Errors ; Peroxisomal Disorders ; Adrenoleukodystrophy

Female ; Humans ; Infant ; Metabolism, Inborn Errors ; Methylmalonic Acid ; blood

Humans ; Infant, Newborn ; Metabolism, Inborn Errors ; diagnosis ; therapy

Child ; Humans ; Carbohydrate Metabolism, Inborn Errors ; Microcephaly ; Psychomotor Disorders ; Seizures

Humans ; Amino Acid Metabolism, Inborn Errors/genetics* ; Haploinsufficiency

OBJECTIVE: To carry out Sanger sequencing for MMACHC gene variants among 65 Chinese pedigrees affected with combined methylmalonic aciduria and homocysteinemia, and summarize their genetic and clinical characteristics and prognosis. METHODS: Clinical characteristics of the 65 children identified with Methylmalonic acidemia and homocysteinemia at the Children's Hospital Affiliated to Zhengzhou University (Zhengzhou Children's Hospital) from April 2017 to April 2022 were selected as the study subjects. Potential variants of the MMACHC gene were detected by direct sequencing of the PCR products. RESULTS: The median age of the 65 children was 3 months (14 days to 17 years old). These included 28 cases (43.08%) from neonatal screening, 11 cases (16.92%) with a history of jaundice, and 9 cases (13.85%) with various degrees of anemia. The main clinical symptoms included development delay, slow growth, epilepsy, hydrocephalus, lethargy, feeding difficulty, regression or decline in motor ability, recurrent respiratory infections, anemia, jaundice, respiratory and heart failures, hydrocephalus, limb weakness, and hypertension. Blood and urine tandem mass spectrometry screening has revealed increase of methylmalonic acid, propionyl carnitine, propionyl carnitine/acetylcarnitine ratio, and propionyl carnitine/free carnitine ratio to various extents, and blood homocysteine was increased in all patients. The detection rate of genetic variants was 98.46% (128/130), and in total 22 types of MMACHC gene variants were detected. The most common ones have included c.609G>A (W203X) (58/128), c.658-660del (K220del) (19/128), and c.80A>G (Q27A) (16/128). Two novel variants have been identified, namely c.565C>T (p.R189C) and c.624_ 625delTG (p.A208Afs), which were respectively predicted as likely pathogenic (PM2_Supporting+PM3+PP2+PP3) and pathogenic (PVS1+PM2_Supporting+PM3+PP2) based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). Exon 4 had the highest frequency for the detection. CONCLUSION Identification of MMACHC gene variants has confirmed the diagnosis in the children, among which the c.609G>A variant has the highest frequency. Discovery of the new variants has enriched the mutational spectrum of the MMACHC gene.
Humans ; Amino Acid Metabolism, Inborn Errors/genetics* ; Hydrocephalus ; Oxidoreductases

Amino Acid Metabolism, Inborn Errors ; Humans ; Infant, Newborn ; Isovaleryl-CoA Dehydrogenase ; deficiency ; Male ; Metabolism, Inborn Errors ; physiopathology