Familial hypercholesterolemia due to ligand-defective apolipoprotein B100: first case report in a Mexican family.
BACKGROUND
Familial defective apolipoprotein B100 (FDB) is one of the known causes of familial hypercholesterolemia (FH). Its frequency among subjects with FH varies among ethnic groups; information on FH is insufficient for populations from Latin America. We proposed to describe prevalence of FDB in a cohort of Mexican FH probands (n = 30).


METHODS
We searched for the known FDB mutations using polymerase chain reaction assays. In this set of patients, mean lipid values were representative of FH (cholesterol 351 mg/dL, LDL cholesterol 274 mg/dL, HDL cholesterol 51 mg/dL, and triglycerides 132 mg/dL).


RESULTS
One subject with Arg3500Gln mutation was found: a 44-year-old male with a history of coronary heart disease (CHD) among paternal relatives. His lipid profile was cholesterol 370 mg/dL, LDL-cholesterol 300 mg/dL, HDL-cholesterol 32 mg/dL, and triglycerides 189 mg/dL. Tendinous xanthomata were detected. Three of four siblings, one of three sons, and one of nine nieces and nephews carried the mutation. The mutation was confirmed by automated sequencing. Tendinous xanthomata were absent in affected subjects younger than age 20 years; additionally, the subjects had borderline cholesterol levels.


CONCLUSIONS
Our data suggest that FDB explains the small number of FH cases in Mexico. Inclusion of molecular biology assays to the clinical laboratory makes it possible to diagnose affected individuals with borderline cholesterol levels or without tendinous xanthomata.
Robles-Osorio
Ludivina
L
Departamento de Endocrinologi;a y Metabolismo, Instituto Nacional de Ciencias Médicas y de Nutrición Salvador Zubirán, Mexico City, Mexico.
Ordoñez
Ma Luisa
ML
Aguilar-Salinas
Carlos A
CA
Aurón-Gómez
Moisés
M
Tusié-Luna
Ma Teresa
MT
Gómez-Pérez
Francisco J
FJ
Rull-Rodrigo
Juan A
JA
D000293:Adolescent; D000328:Adult; D000368:Aged; D053299:Apolipoprotein B-100; D001055:Apolipoproteins B / Q000235:genetics / Q000378:metabolism*; D002648:Child; D005260:Female; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000453:epidemiology / Q000235:genetics / Q000378:metabolism*; D008055:Lipids / Q000097:blood; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D010375:Pedigree; D017354:Point Mutation
D053299:Apolipoprotein B-100; D001055:Apolipoproteins B; D008055:Lipids