| Title | Identification of patients with abetalipoproteinemia and homozygous familial hypobetalipoproteinemia in Tunisia. | | Author(s) | Najah M, Di Leo E, Awatef J, Magnolo L, Imene J, Pinotti E, Bahri M, Barsaoui S, Brini I, Fekih M, Slimane MN, Tarugi P | | Institution | Research Unit of Genetic and Biologic Factors of Atherosclerosis, Faculty of Medicine, Monastir, Tunisia. | | Source | Clin Chim Acta 2008 Nov 21. | | Abstract | BACKGROUND: Abetalipoproteinemia (ABL) and Homozygous Familial Hypobetalipoproteinemia (Ho-FHBL) are rare monogenic diseases characterised by very low plasma levels of cholesterol and triglyceride and the absence or a great reduction of apolipoprotein B (apoB)-containing lipoproteins. ABL results from mutations in the MTP gene; Ho-FHBL may be due to mutations in the APOB gene.
METHODS: We sequenced MTP and APOB genes in three Tunisian children, born from consanguineous marriage, with very low levels of plasma apoB-containing lipoproteins associated with severe intestinal fat malabsorption.
RESULTS: Two of them were found to be homozygous for two novel mutations in intron 5 (c.619-3T>G) and in exon 8 (c.923 G>A) of the MTP gene, respectively. The c.619-3T>G substitution caused the formation of an abnormal mRNA devoid of exon 6, predicted to encode a truncated MTP of 233 amino acids. The c.923 G>A is a nonsense mutation resulting in a truncated MTP protein (p.W308X). The third patient was homozygous for a novel nucleotide deletion (c.2172delT) in exon 15 of APOB gene resulting in the formation of a truncated apoB of 706 amino acids (apoB-15.56).
CONCLUSIONS: These mutations are expected to abolish the apoB lipidation and the assembly of apoB-containing lipoproteins in both liver and intestine. | | Language | ENG | | Pub Type(s) | JOURNAL ARTICLE
| | PubMed ID | 19056372 |
|
