title: The APOB insertion/deletion polymorphism (rs17240441) influences postprandial lipaemia in healthy adults.
abstract: BACKGROUND
  Apolipoprotein (apo)B is the structural apoprotein of intestinally- and liver- derived lipoproteins and plays an important role in the transport of triacylglycerol (TAG) and cholesterol. Previous studies have examined the association between the APOB insertion/deletion (ins/del) polymorphism (rs17240441) and postprandial lipaemia in response to a single meal; however the findings have been inconsistent with studies often underpowered to detect genotype-lipaemia associations, focused mainly on men, or with limited postprandial characterisation of participants. In the present study, using a novel sequential test meal protocol which more closely mimics habitual eating patterns, we investigated the impact of APOB ins/del polymorphism on postprandial TAG, non-esterified fatty acids, glucose and insulin levels in healthy adults.
  
  
  RESULTS
  Healthy participants (n = 147) consumed a standard test breakfast (0 min; 49 g fat) and lunch (330 min; 29 g fat), with blood samples collected before (fasting) and on 11 subsequent occasions until 480 min after the test breakfast. The ins/ins homozygotes had higher fasting total cholesterol, LDL-cholesterol, TAG, insulin and HOMA-IR and lower HDL-cholesterol than del/del homozygotes (P < 0.017). A higher area under the time response curve (AUC) was evident for the postprandial TAG (P < 0.001) and insulin (P = 0.032) responses in the ins/ins homozygotes relative to the del/del homozygotes, where the genotype explained 35% and 7% of the variation in the TAG and insulin AUCs, respectively.
  
  
  CONCLUSIONS
  In summary, our findings indicate that the APOB ins/del polymorphism is likely to be an important genetic determinant of the large inter-individual variability in the postprandial TAG and insulin responses to dietary fat intake.
authors: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, Reading, RG6 6AP UK ; Institute for Cardiovascular and Metabolic Research (ICMR), University of Reading, Reading, UK.
authors: Karani Santhanakrishnan
authors: KS
authors: Vimaleswaran
authors: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, Reading, RG6 6AP UK ; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, UK.
authors: Anne M
authors: AM
authors: Minihane
authors: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, Reading, RG6 6AP UK ; Institute for Cardiovascular and Metabolic Research (ICMR), University of Reading, Reading, UK.
authors: Yue
authors: Y
authors: Li
authors: Boston Heart Diagnostics, Framingham, MA 01702 USA.
authors: Rosalyn
authors: R
authors: Gill
authors: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, Reading, RG6 6AP UK ; Institute for Cardiovascular and Metabolic Research (ICMR), University of Reading, Reading, UK.
authors: Julie A
authors: JA
authors: Lovegrove
authors: Institute for Cardiovascular and Metabolic Research (ICMR), University of Reading, Reading, UK.
authors: Christine M
authors: CM
authors: Williams
authors: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading, Reading, RG6 6AP UK ; Institute for Cardiovascular and Metabolic Research (ICMR), University of Reading, Reading, UK.
authors: Kim G
authors: KG
authors: Jackson
keywords: APOB gene; Insertion/deletion polymorphism; Postprandial study; Sequential test meals; Signal peptide polymorphism; Triacylglycerol