Variable phenotypic expression of chylomicron retention disease in a kindred carrying a mutation of the Sara2 gene.
Chylomicron retention disease is a recessive inherited disorder characterized by fat malabsorption and steatorrhea and is associated with failure to thrive in infancy. We describe a kindred carrying a mutation of Sara2 gene causing a chylomicron retention phenotype. The proband was a 5-month-old baby, born of consanguineous, apparently healthy parents from Morocco, with failure to thrive. There was a large quantity of fats in feces and malabsorption of fat-soluble vitamins. Intestinal biopsies showed a diffused enterocyte vacuolization with large cytosolic lipid droplets. Chylomicron retention disease or Anderson disease was hypothesized, and the Sara2 gene was analyzed by direct sequencing. Analysis of the Sara2 gene in the proband identified a 2-nucleotide homozygous deletion in exon 3 leading to a premature stop codon (c.75-76 del TG-L28fsX34). The father was heterozygous for the same mutation, whereas the proband's mother was homozygous, suggesting a variable phenotypic expression of the molecular defect. More studies are needed to understand the reasons of the phenotypic variability of the same molecular defect in the same family.
Departmet of Clinical Medicine and Emerging Diseases, University of Palermo, I-90127 Palermo, Italy.
Angelo B
AB
Cefalù
Pier L
PL
Calvo
Davide
D
Noto
Maurizio
M
Baldi
Vincenza
V
Valenti
Pietro
P
Lerro
Fabio
F
Tramuto
Antonella
A
Lezo
Isabella
I
Morra
Giovanna
G
Cenacchi
Cristiana
C
Barbera
Maurizio R
MR
Averna
D000328:Adult; D002675:Child, Preschool; D002914:Chylomicrons / Q000378:metabolism*; D000795:Fabry Disease; D005260:Female; D006801:Humans; D007223:Infant; D008286:Malabsorption Syndromes / Q000235:genetics*; D008297:Male; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics*; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D045602:Steatorrhea / Q000235:genetics*
D002914:Chylomicrons; C513282:SAR1B protein, human; D020559:Monomeric GTP-Binding Proteins