Whole Exome Sequencing (WES) is currently a solid diagnostic tool for heterogeneous genetic diseases. However, a partial and insufficient analysis of WES data could lead to mis diagnosis. We compiled 13 cases, most of them with previous negative WES results, in which a thorough reanalysis of the data yielded new candidate genes with diagnostic potential.

Familial X-linked hypophosphatemic rickets (XLHR) is defined as a group of disorders characterized by rickets with bone deformities, short stature, dental anomalies, hypophosphatemia and increased activity of serum alkaline phosphatases. According to the bibliography, pathogenic variants in the PHEX gene are the most common cause of XLHR and only a few cases of mosaicism have been […]

Knowing that we find ourselves in the Genomic Era, where researchers and clinicians have started to use the knowledge of genomics to improve health; the presence of genetic counsellors are becoming increasingly necessary within laboratories themselves. The current demand in both public and private centres for exomic and genomic tests […]

Partial duplications and deletions in the same chromosome are very rare events, usually sporadic They could be due to a parental paracentric inversion of that chromosome, non allelic homologous recombination (or to an abnormal cross linking during meiosis. Also, the phenotypic expression of both aneuploidies could be highly variable and the etiological mechanism is complex […]

Knowing that we find ourselves in the Genomic Era, where researchers and clinicians have started to use the knowledge of genomics to improve health the presence of genetic counsellors are becoming increasingly necessary within laboratories themselves The current demand in both public and private centres for exomic and genomic tests shows the importance of conducting genetic […]

Methylmalonic acidaemia with homocystinuria is an infrequent inborn error of vitamin B12 (cobalamin) metabolism. It is caused by defects in the synthesis of the coenzymes adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl), leading to decreased activity of the corresponding enzymes methylmalonyl-CoA mutase (MUT;609058) and 5-methyltetrahydrofolate-homocysteine methyltransferase, also known as methionine synthase […]

Vitamin B12 (cobalamin) is metabolised to methylcobalamin and adenosylcobalamin, two essential coenzymes for maintaining intracellular homeostasis of homocysteine (HC) and methylmalonic acid (MMA). Acquired or inherited imbalances in the metabolism of cobalamin (Cbl) can lead to accumulations of HC and/or MMA in plasma and urine […]

Methylmalonic acidemia with homocystinuria, included in the remethylation disorders of homocysteine to methionine, is a rare congenital error of vitamin B12 metabolism (cobalamin). There are four complementation groups of cobalin defects (cblC, cblD, cblF and cblJ), associated with methylmalonic acidemia with homocystinuria (MMA/HC). The defect causes decreased levels of the coenzymes adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl), which lead to decreased activity of the respective enzymes methylmalonyl-CoA mutase and methionine synthase. CblD-MMA/HC is caused by mutations in the MMADHC gene (2q23.2) with an autosomal recessive inheritance pattern […]