Hyperlipidemia, Familial Combined, 2

Description

Familial combined hyperlipidemia (FCHL) is characterized by fluctuations in serum lipid concentrations and may present as mixed hyperlipidemia, isolated hypercholesterolemia, hypertriglyceridemia, or as a normal serum lipid profile in combination with abnormally elevated levels of apolipoprotein B (APOB; 107730). Patients with FCHL are at increased risk of cardiovascular disease and mortality and have a high frequency of comorbidity with other metabolic conditions such as type 2 diabetes, nonalcoholic fatty liver disease, steatohepatitis, and the metabolic syndrome (summary by Bello-Chavolla et al., 2018).

For a phenotypic description and a discussion of genetic heterogeneity of familial combined hyperlipidemia, see 144250.

Mapping

Using a subset of 35 Dutch families ascertained for FCHL, Aouizerat et al. (1999) screened the genome, with a panel of 399 genetic markers, for chromosomal regions linked to FCHL. The results were analyzed by parametric-linkage methods in a 2-stage study design. Suggestive evidence for linkage with FCHL (lod scores of 1.3 to 2.6) was found at 2p, 11p, 16q, and 19q. Markers within each of these regions were then examined in the original sample and in additional Dutch families with FCHL. The locus on chromosome 2 failed to show evidence for linkage, and the loci on 16q and 19q yielded equivocal or suggestive evidence for linkage. However, 1 locus, near marker D11S1324 on the short arm of chromosome 11, continued to show evidence for linkage with FCHL in the second stage of the study.