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Abstract-Familial combined hyperlipidemia (FCHL) is the most frequent familial lipoprotein disorder associated with premature coronary heart disease. However, no genetic defect(s) underlying FCHL has been identified. A linkage between FCHL and the apoA-I/C-III/A-IV gene cluster has been reported but not verified in other populations. A recent study identified FCHL susceptibility haplotypes at this gene cluster. To study whether such haplotypes are also associated with FCHL susceptibility in Finns, we studied 600 well-defined Finnish FCHL patients and their relatives belonging to 28 extended FCHL families by using haplotype, linkage, sib-pair, and linkage disequilibrium analyses. Key Words: apoA-I Ⅲ apoC-III Ⅲ apoA-IV Ⅲ familial combined hyperlipidemia Ⅲ coronary heart disease F amilial combined hyperlipidemia (FCHL), originally described by 3 independent groups, 1-3 is characterized by an elevation of cholesterol and/or triglyceride levels. In Western societies, the condition is found in 1% to 2% of the population and in Ϸ10% of survivors of myocardial infarction, designating FCHL as one of the most frequent familial dyslipidemias associated with premature coronary heart disease (CHD). In affected subjects, a common characteristic is an increase in small, dense LDL particles.4-6 A consistent metabolic finding in FCHL is an increased apoB plasma level, 7,8 which is due to either increased production or lowered clearance of apoB-containing lipoproteins. 9 -11 Association between the apoA-I/C-III/A-IV gene cluster on chromosome 11 and FCHL has been the subject of several studies. An association between FCHL and an XmnI restriction fragment polymorphism in the 5Ј-flanking region of the apoA-I gene was reported, 12 and the finding was later confirmed by linkage (logarithm of the odds [lod] score, 6.86) without recombinants in 7 families. 13 Further evidence for an association between this gene cluster and FCHL has been provided by other groups, 14 -16 but the findings have also been challenged, [17][18][19][20] and the positive linkage result has not been confirmed. An explanation for this controversy may be provided by a recent study, 21 in which the contribution of the apoA-I/C-III/A-IV gene cluster is presented as an epistatic interaction between different haplotypes, a finding that may also partially explain the paradigm of the complex and varying phenotypes of FCHL. A specific combination of haplotypes (1-1-2/2-2-1, "the high-risk haplotype combination") derived from polymorphic XmnI and MspI sites in the 5Ј-flanking region of the apoA-I gene and the SstI site in the 3Ј-untranslated region of the apoC-III gene was reported to be more frequent in hyperlipidemic patients (frequency, 0.06) than in normolipidemic relatives (frequency, 0.03, PϽ0.05) or spouses (frequency, 0.005, Pϭ0.01). The aim of the current study was to test whether these specific haplotypes are also associated with FCHL in Finnish FCHL families. Methods Study SubjectsThe collection of carefully documented pedigrees with several affected indivi...

Wood defects and grain angle correlate strongly with timber strength and grading. In this study a laser transillumination imaging method was developed to determine wood defects and grain angle. The method uses a near infrared laser light source which illuminates a wood sample with a round beam and the image generated by the light transmitted through the sample is captured for further analysis. In basic and flawless wood, the transmitted light pattern is an ellipse and wood defects and grain angle deviation will change the shape, size and location of the ellipse. The method could be used for determining the strength of wood, grading sawn timber, studying finger and glue joints, estimating moisture and differentiating between heartwood and sapwood.