Abstract: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder of lipid metabolism, associated with elevated levels of low-density lipoprotein-cholesterol (LDLC), which can lead to premature cardiovascular disease and early death. Early diagnosis and initiation of treatment is important to prevent morbidity and mortality. Autosomal dominant hypercholesterolemia (ADH) is largely due to mutations in the low-density lipoprotein receptor gene (LDLR), the apolipoprotein B-100 gene (APOB), or the proprotein convertase subtilisin/kexin type 9 (PCSK9). In this study, genomic DNA of unrelated Libyan individuals with clinically diagnosed (FH) was analyzed by direct sequencing after dependent specific PCR primers amplification and DNA purification. That led to the identification of PCSK9 gene mutations for the first time in Libyan population which was compare to other populations. All 12 exons of PCSK9 gene and boundaries genotyped polymorphisms were sequenced, including leucine repeats coded in exon 1, by fluorescently tagged markers. We identified an allele for the rs67610340 polymorphism: an in-frame deletion, c.61_63delCTG (L8). We also identified another allele rs67610340 polymorphism: an in frame insertion c.61_63InsCTG (L10). The insertion and deletion alleles were both in exon 1 and could be associated with a risk and severity of coronary artery disease (CAD), suggesting a direct effect of PCSK9 on atherogenesis. arabic 11 English 90
Ghada Salem, Ahmed Zaid(1-2017)

Background: Phenylketonuria (PKU) is one of the most common inborn errors of amino acids metabolism. It is an autosomal recessive disease that is caused by mutations in phenylalanine hydroxylase (PAH) gene. In the North Africa and Eastern Mediterranean region, E280K missense mutation and c.1055del.G frameshift mutation in PAH gene are one of the most common pathogenic mutations seen in PKU patients. Materials and Methods: In this study, we developed molecular protocols for rapid screening of the PKU patients for these two mutations. These protocols are based on hydrolysis probe real-time polymerase chain reaction technique using allele-specific probes labeled with 6-carboxyfluorescein (FAM) for wild-type (WT) and hexachloro-6-carboxyfluorescein (HEX) for mutant genotypes and Black Hole Quencher 1 as a quencher and high-resolution melting analysis using EvaGreen saturating dye. Results: There was complete accordance between the developed protocols in differentiating genotypes and they proved to be rapid, sensitive, and efficient for the detection and differentiation between WT, mutant, and heterozygous genotypes of the E280K and c.1055del.G mutations. Conclusions: These protocols allow easy molecular screening of the mutations studied among the families of affected people, especially for premarital screening. arabic 27 English 170
Abdulla Bashein(1-2017)

Objective: In Libya, no pertussis booster doses are administered to children after 18 months of age. In light of evidence of waning of vaccine-induced immunity to pertussis, this study aimed to evaluate the waning of immunity in vaccinated school-entry age children, as measured by susceptibility to infection at population level. For this purpose, IgG and IgA levels were measured as markers of recent (infection in the last 6 months) and non-recent infections (infection in the last 12 months). Material and Methods: This was a cross sectional study undertaken in Tripoli, in February 2015. Children of school-entry age (> 5 to ≤ 7 years) were recruited on convenience basis at vaccination centers. Sera were tested for antibodies to pertussis. Results: Samples from791 children (421 males and 370 females, mean age 6.50 were tested). All of the participants had received 4 doses of Whole cell pertussis containing vaccine in the first 2 years of life. The prevalence of recent and non-recent pertussis infection were 4.8% and 2.5%, respectively. The proportion of children with undetectable level of IgG was 76.1%. Conclusion: The findings of this study showed significant circulation of Bordetella pertussis among vaccinated children by school-entry age. The circulation of B. pertussis in this population may be an indirect sign of waned immunity, which is simply corroborated by the absence of detectable antibodies in 76.1% of the children. arabic 14 English 76
Suleiman Abusrewil, Abdulla Bashein(1-2019)