Mutation detection by analysis of DNA heteroduplexes in TILLING populations of diploid species

In the beginning of mutation research, mutations could only be detected indirectly through the analysis of the phenotypic alterations that they caused. The detection of mutations at the DNA level became possible with the development of sequencing methods. Nowadays, there are many different methods and strategies that have been created for mutation detection, both in natural and mutagenised populations. The strategies differ in accuracy and sensitivity, as well as in the laboratory facilities, time, costs and efforts that are required. The majority of them involve the pooling of DNA samples and the amplification of a gene (fragment) of interest followed by heteroduplex formation. One of the popular strategies for mutation identification takes advantage of the specific endonuclease (e.g. CEL I) that recognises and cuts heteroduplexes precisely at the 3′ position of the mismatch site. The cleaved fragments are usually visualised through electrophoresis in a polyacrylamide gel using LI-COR sequencers, but agarose electrophoresis may also be used for this purpose, although with less sensitivity. A different mutation identification strategy, which is based on the high-resolution melting (HRM) technique, may be the method of choice when working with a short gene or a gene fragment whose length optimally does not exceed 400 bp

Severe infantile hypotonia with ethylmalonic aciduria: Case report

An 8-month-old girl was admitted to an outpatient clinic with significant hypotonia and weakness. Organic acid analysis in urine revealed a significant increase in ethylmalonic acid. A deoxyribonucleic analysis revealed the presence of a 625G>A (G-to-A substitution at nucleotide 625) variant short-chain acyl-coenzyme A dehydrogenase gene polymorphism. With the clinical, biochemical and molecular findings, short-chain acyl-coenzyme A dehydrogenase deficiency was suspected. Because 625G>A and 511C>T (C-to-T substitution at nucleotide 511) genetic variations are also present in 14% of the general population, these are considered to be genetic sensitivity variations rather than causing a disease themselves and to result in possible short-chain acyl-coenzyme A dehydrogenase deficiency in the presence of environmental factors such as fever and hunger as well as cellular, biochemical, and other genetic factors. It was stressed that severe infantile hypotonia could also be the only manifestation of ethylmalonic aciduria spectrum disorders. \ua9 2008 Sage Publication

A 7-YEAR-OLD BOY WITH HAND TREMORS AND A NOVEL MUTATION FOR L-2-HYDROXYGLUTARIC ACIDURIA

L-2-hydroxyglutaric aciduria (L2HGA), which is a rare autosomal recessive metabolic disorder caused by mutations in the encoding L2HGDH gene. Neurological symptoms are the main predominant clinical signs. The distinctive feature is the specific multifocal lesion of the white matter detected on magnetic resonance imaging (MRI). A 7-year-old male patient of Turkish origin was admitted to the hospital because of hand tremors. Physical examination revealed macrocephaly, intention tremors, walking disability and ataxic gait. Urine organic acid analysis showed increased excretion of L-2-hydroxyglutaric acid (L2HG acid). Analysis of the L2HGDH gene revealed a novel homozygous c.368A>G, p. (Tyr123Cys) mutation. L-2-hydroxyglutaric aciduria is a cerebral organic aciduria that may lead to various neurological complications. Early recognition of symptoms of L2HGA is important for initiation of supportive therapy that may slow down the progression of the disease

Severe neonatal hypercalcemia caused by subcutaneous fat necrosis without any apparent cutaneous lesion.

International audienceSubcutaneous fat necrosis is a classic, albeit uncommon, cause of neonatal hypercalcemia. It occurs in newborn infants within the first month of life following a complicated delivery. The diagnosis is usually easy because of the presence of red-purple plaques in fatty areas along with firm subcutaneous nodules. A 1-month-old neonate, born strangled by her umbilical cord, presented with diarrhea and hypercalcemia (3.46 mM) with an initial physical examination considered normal. Her biological evaluations were as follows: P = 1.37 mM (1.6-2.2); PTH = 3 ng/L (12-65); 25-OH vitamin D = 87 nM (23-113); (1,25)-OH(2) vitamin D = 192 ng/L (20-46). The third day, a careful exam of the whole cutaneous surface revealed small firm subcutaneous nodules in the ischial region. Despite the absence of any visible skin modification, the association of perinatal stress and high (1,25)-OH(2) vitamin D level with subcutaneous nodules led to the diagnosis of subcutaneous fat necrosis. She was treated with oral prednisone for 45 days. Serum calcium levels normalized within a week, and the nodules disappeared without complications. Conclusion: Subcutaneous fat necrosis may induce severe hypercalcemia without any visible cutaneous lesion

EFFICACY AND SAFETY OF SEBELIPASE ALFA IN CHILDREN AND ADULTS WITH LYSOSOMAL ACID LIPASE DEFICIENCY: RESULTS OF A PHASE 3 TRIAL

50th International Liver Congress of the European-Association-for-the-Study-of-the-Liver -- APR 22-26, 2015 -- Vienna, AUSTRIAWOS: 000362830900402European Assoc Study Live