[24-bp duplication on CHIT1 gene in Mexican population]

BACKGROUND

human chitotriosidase is a secreted enzyme by activated macrophages, detectable in plasma. Levels of chitotriosidase indicate severity of Gaucher disease and monitoring the efficiency of the enzyme replacement therapy. The most frequent polymorphism in chitotriosidase-1 gene (CHIT1) corresponds to a 24-bp duplication (24-bp Dup) that in homozygotes individuals gives place to the enzyme inactivation. The objective was to identify in a sample of Mexican health population the 24-bp Dup in CHIT1 gene and determinate the allelic and genotypic frequencies.

METHODS

306 DNA samples of healthy individuals were analyzed in polyacrylamide gels and the allelic and genotypic frequencies was determined with SPSS v. 13.0.

RESULTS

distribution of the 24-bp Dup was in accordance to Hardy-Weinberg equilibrium (p = 0.90), with an allelic frequency of 23.86 %. Genotypic frequencies for homozygous and hetero-zygotes were of 5.56 % and 36.60 % respectively.

CONCLUSIONS

allelic and genotypic frequencies of the 24-bp Dup in CHIT1 gene in homozygotes and heterozygotes were in accordance to worldwide reports.

[Therapy of lysosomal storage diseases: update and perspectives]

Lysosomal storage diseases (LSD) are caused by monogenic mutations in genes coding for multiple aberrant proteins involved in the catabolism of complex lipids, glycosaminoglycans, oligosaccharides, or nucleic acids. The pathophysiology of the LSD is due to abnormal accumulation of non-hydrolyzed substrate in the lysosomes, affecting the architecture and function of cells, tissues and organs. Due to their genic and allelic heterogeneity the LSD present a wide clinical spectrum in severity of symptoms, evolution and age of onset. The therapeutic strategy has two goals: 1) Palliative management of symptoms (splenectomy, surgery to improve or restore joints or bones, drugs for CNS symptoms, etc.), and 2) The correction of activity of the mutant protein, the former has two approaches: A) Replacing deficient protein (bone marrow transplantation, hematopoietic stem cells or umbilical cord blood cells; replacement with recombinant enzyme and gene therapy) and B) Activate or enhanced the functionality of the mutant enzyme with therapeutic small molecules. Neither of the known treatments is able to address all aspects of these multisystemic disorders, nor cure the patients. Currently, the combination of corrective therapy (CT) with paliative therapy (PT) is the most promising strategy to solve most of the multisystem manifestations. The multidisciplinary medical care is fundamental for diagnosis, treatment and control of disease. Nanotechnology opens a promising new era in the treatment of LSD. Finally, the LSD that has CT must be included in newborn screening programs in order to implement timely treatment and prevent irreversible damage.