Premium
Heterozygous apolipoprotein C‐II deficiency: lipoprotein and apoprotein phenotype and Rsal restriction enzyme polymorphism in the Apo C'IIPadova kindred
Author(s) -
GABELLI C.,
BILATO C.,
SANTAMARINAFOJO S.,
MARTINI S.,
JR H. B. BREWER,
CREPALDI G.,
BAGGIO G.
Publication year - 1993
Publication title -
european journal of clinical investigation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.164
H-Index - 107
eISSN - 1365-2362
pISSN - 0014-2972
DOI - 10.1111/j.1365-2362.1993.tb00960.x
Subject(s) - phenotype , apolipoprotein b , genetics , biology , polymorphism (computer science) , restriction enzyme , lipoprotein , enzyme , allele , gene , endocrinology , biochemistry , cholesterol
. Deficiency of apolipoprotein C‐II (apo C‐II), the cofactor for lipoprotein lipase, results in the familial chylomicronaemia syndrome characterized by severe hypertriglyceridaemia and fasting chylomicronaemia. To investigate the biochemical features of the heterozygous state for apo C‐II deficiency, we characterized the lipid, lipoprotein and apolipoprotein profiles in 18 relatives of two affected individuals (brother and sister) homozygous for the apo C‐II Padova gene defect which results in the synthesis of a truncated 36 amino acid apolipoprotein. Carrier status was established in first degree relatives as well as in seven non‐obligate heterozygotes by restriction enzyme analysis of amplified apo C‐II genomic DNA using RsaI. No significant differences in lipid, lipoprotein and apo C‐II levels were observed in heterozygotes when compared to unaffected family members. Thus, in this study, the carrier state was not associated with hypertriglyceridaemia or reduced plasma levels of apo C‐II. However, analysis of amplified DNA from members of the apo C‐II Psdova kindred by digestion with the enzyme RsaI, which identifies the mutant apo C‐II, permitted the identification of heterozygous family members which could not be recognized by measuring either fasting triglycerides or plasma apo C‐II levels. This study provides further evidence that apo C‐II deficiency syndrome is a heterogeneous disease not only at the molecular level but also on the clinical ground with variable phenotypic expression in heterozygous individuals from different kindreds.