JMIR Publications

ABSTRACT

Background:

Mucopolysaccharidosis IVA (MPS IVA), also known as Morquio syndrome, is a rare autosomal recessive lysosomal storage disease resulting from mutations in the N-acetylgalactosamine-6-sulfatase (GALNS) gene. This leads to a deficiency of the GALNS enzyme, causing the accumulation of glycosaminoglycans (GAGs) in tissues. Morquio syndrome primarily affects the skeletal system and joints but can also impact various organs, resulting in symptoms such as hearing and vision loss, respiratory issues, spinal cord compression, heart diseases, and hepatomegaly. The genotype-phenotype relationship is diverse, with studies highlighting variants associated with classic, non-classic, or intermediate phenotypes. Understanding these genetic factors is crucial for predicting disease prognosis and tailoring effective treatment strategies for individuals with Morquio syndrome.

Objective:

The aim of this systematic review is to comprehend the relationship between the severity of the phenotype and the genotype of MPS IVA patients, considering factors such as the type of variant and its location in the different domains of the protein.

Methods:

This systematic review includes participants of all genders and age groups with a molecular diagnosis of MPS IVA, along with a description and/or classification of the phenotype. No exclusion criteria based on country, language, or document type will be applied. The information sources considered will encompass experimental and quasi-experimental studies, analytical observational studies, observational studies, and qualitative research. Unpublished literature will not be included. The screening of literature, paper selection, and data extraction will involve two independent reviewers who will conduct the process blindly. In the event of disagreements between the two reviewers at any stage, resolution will be sought through discussion or with the involvement of an additional reviewer. The final selection of manuscripts will be based on consensus. The results of the review will be presented using descriptive statistics, and the information will be organized in either diagrammatic or tabular formats, following the guidelines provided by JBI (Joanna Briggs Institute's).

Results:

The literature search was conducted in January 2024 using PubMed, MEDLINE, ScienceDirect, and Scopus A total of 760 results were retrieved. The review is expected to be completed by the end of 2024.

Conclusions:

This scoping review and meta-analysis will be the first to gather and analyze information on the phenotype-genotype relationship in patients diagnosed with MPS IVA. The data collection and resulting analyses will make a substantial contribution to understanding the underlying mechanism of the disease, enabling the prediction of the syndrome's progression and severity. This, in turn, will assist in guiding medical interventions with greater precision and effectiveness.