What kind of mutation is galactosemia

Novelli G, Reichardt JK: Molecular basis of disorders of human galactose metabolism: past, present, and future.

Mol Genet Metab Sep-Oct;71 Skip to main content. Register Sign In. Test Catalog Account. Outreach Solutions Tactics Articles Events. Utilization Management Algorithms. Test Catalog. Download Test. Useful For Suggests clinical disorders or settings where the test may be helpful Second-tier test for confirming a diagnosis of galactosemia indicated by enzymatic testing or newborn screening Carrier testing family members of an affected individual of known genotype has mutations included in the panel Resolution of Duarte variant and Los Angeles LA variant genotypes.

An interpretative report will be provided. Results should be interpreted in the context of biochemical results. In rare cases, DNA alterations of undetermined significance may be identified.

RH mutation. Both showed a good clinical outcome. The first was diagnosed through expanded neonatal screening test and therefore started treatment early. The second one was with jaundice and hepatomegaly at 15 days of age and was diagnosed a month later, when in addition, he presented cataracts.

The most common variant of the gene is the Duarte D2 allele, that is generally not associated with a clinical phenotype when in homozygous, and when in heterozygous with a disease-causing mutation can trigger a mild form of galactosemia called Duarte galactosemia [ 23 ]. This individual is asymptomatic, even without diet restriction and despite the low enzymatic activity, therefore it is not possible to establish whether this new mutation is pathogenic or not, additional functional studies are necessary.

GD and had only prolonged neonatal jaundice. This patient has an enzyme assay below the normal range and was in a galactose restriction diet. The patient heterozygous for the p. Definitely, with the availability of neonatal screening test for Galactosemia routinely in some countries, the clinical outcome improved a lot. The greatest benefit derived from this approach is that it is possible to introduce therapy before the onset of acute severe complications.

However, it is noteworthy that not every positive test is followed by the diagnosis of CG. Many positive tests are due to variant Duarte and some to other forms of Galactosemia. Therefore, after a positive test, it is important apart from starting treatment, make quickly a careful clinical assessment and perform genotyping, in order to determine whether the patient will be kept in galactose restriction diet.

Genetic heterogeneity documented to date, undoubtedly contributes to the phenotypic heterogeneity that is observed in galactosemia. Additional effects of non-allelic variation and other constitutional factors on phenotypic variability remain to be elucidated.

The present study characterized the phenotypic and genotypic profile of some patients with classic galactosemia in the Brazilian population, which is considered one of the most heterogeneous in the world, as a result of more than five centuries of miscegenation among mainly three ancestral roots: the indigenous Amerindians, Europeans and sub-Saharan Africans.

The heterogeneity and admixture have important implications in the current genetic background of the population [ 42 , 43 ] that has a high estimated prevalence of CG compared with other populations [ 28 ]. This is the first genotyping study in Brazilian patients with diagnosis of Galactosemia. Biosynthesis of glycogen from uridine diphosphate glucose.

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Xu, Y. Polymorphism of erythrocyte galactosephosphate uridyltransferase among Chinese. A number sign is used with this entry because galactosemia I, or classic galactosemia, is caused by homozygous or compound heterozygous mutation in the galactosephosphate uridylyltransferase gene GALT; on chromosome 9p Using G for the allele causing classic galactosemia and D for the Duarte allele ND; rs; NOTE: OMIM is intended for use primarily by physicians and other professionals concerned with genetic disorders, by genetics researchers, and by advanced students in science and medicine.

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