Lipa Gene Mutation in PED-LIPIGEN (Pediatric FH Subjects)
-
- STATUS
- Recruiting
-
- End date
- Jul 1, 2023
-
- participants needed
- 1000
-
- sponsor
- Fondazione SISA (Societa Italiana per lo Studio della Arteriosclerosi)
Summary
Familial Hypercholesterolemia (FH) is a monogenic autosomal dominant disease also known as Autosomal Dominant Hypercholesterolemia - ADH) that leads to dramatically increased levels of Low Density Lipoprotein (LDL) and total cholesterol associated to tendon xanthomas, xanthelasma, corneal arcus, premature atherosclerosis and to an increased risk of coronary artery disease (CAD) and myocardial infarction.
FH is mainly caused by mutations in genes encoding for proteins affecting hepatic LDL cholesterol uptake including the LDL receptor (LDLR) gene or the gene encoding the only apolipoprotein of LDL, the apolipoprotein B (APOB), or the gene encoding a protease regulating LDLR levels on the cell membrane Lysosomal Acid Lipase A (LIPA) gene encode for Lysosomal acid lipase (LAL) enzyme responsible for hydrolyzing cholesterol esters and triglycerides that are delivered to lysosomes. Mutations in LIPA that completely inactivate LAL are the molecular cause of Wolman disease, a rapidly lethal disease of infancy while mutations in LIPA that result in residual enzymatic activity of LAL are responsible of a disorder characterized by a less severe phenotype known as cholesterol ester storage disease (CESD). Patients with CESD usually show a phenotype characterized by hepatic disease and mixed hyperlipidemia with elevated levels of LDL-C and triglycerides (TG) and decreased HDL-C levels.
A broader phenotypic presentation for loss of function mutations in LIPA suggests that LIPA mutations may be considered in patients with apparently monogenic FH in whom mutations in the known candidate genes are not detectable.
The project is aimed to evaluate the prevalence and the mutation rate of LIPA gene in subjects with a clinical diagnosis of FH and already genetically characterized in whom pathogenic mutations in the known candidate genes have not been identified. The analysis will be performed in about 250 FH pediatric subjects and putative causal mutations will be also tested for co-segregation in available families in affected and unaffected members.
Description
Lysosomal acid lipase (LAL) is encoded by LIPA gene located on chromosome 10q23.3-q23 and consists of 10 exons. LIPA mRNA (messenger RiboNucleic Acid) (GenBank accession number NM_000235) is 2782 bp long and encodes a mature protein of 375 residues (GenBank accession number NP_000226). The sequencing of all 10 exons of LIPA gene will consist of 10 PCR (Polymerase Chain Reaction) amplification reactions (for the 10 exons and the proximal promoter) followed by 20 sequence reactions (forward and reverse sequencing) with appropriate primers designed to include the intron-exon boundaries. This analysis will be performed in about 250 FH pediatric subjects as specified in project description.
The sequencing work will be performed taking advantage of 2 automated 8 capillaries automated DNA Sequencer (3500 Genetic Analyzer, Thermo Fisher Scientific, Monza, Italy) currently available in the laboratory of the Units involved in the project.
In case of identification of unreported sequence variants, the presence of these mutations will be assessed in a sample of at least 100 normolipidemic subjects of the population, in order to define whether the nucleotide changes are rare sequence variations (with a putative functional effect) or represent common polymorphisms. In case of finding of rare variants in the coding regions, an in silico analysis will be performed by using two different softwares (Polyphen, http://genetics.bwh.harvard.edu/pph/ and Panther, http://www.pantherdb.org/) to predict the putative damaging role of the mutations on the protein. In case of intronic variants, the specifically designed software Automated Splice Site Analysis will be applied (https://www.splice.uwo.ca/).
Putative causal mutations will be also tested for co-segregation in available families in affected and unaffected members.
In order to test the effect of variants on enzyme activity LAL-activity will be assayed with dried blood spot (DBS) technique using the inhibitors Lalistat 2 in carriers and non carriers of these mutations belonging to available kindred.
Details
| Condition | Lysosomal Acid Lipase Deficiency |
|---|---|
| Treatment | Observational study |
| Clinical Study Identifier | NCT03984149 |
| Sponsor | Fondazione SISA (Societa Italiana per lo Studio della Arteriosclerosi) |
| Last Modified on | 4 October 2022 |
How to participate?
,
You have contacted , on
Your message has been sent to the study team at ,
What happens next?
- You can expect the study team to contact you via email or phone in the next few days.
- Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.
You are contacting
Primary Contact
Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.
Learn moreIf you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.
Learn moreComplete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.
Learn moreSimilar trials to consider
Browse trials for
Not finding what you're looking for?
Sign up as a volunteer to stay informed
Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.
Sign up as volunteer