Apo B48 & Apo B100 are synthesised from same mRNA due to difference in:

Apo B48 & Apo B100 are synthesized from same mRNA due to difference in RNA Editing/Chemical modification of RNA/ Differential RNA Processing In theliver, apo B mRNA is 100% translated to produceapoB100protein. In theintestine,the same apo B mRNA is acted upon by the cytosine deaminase enzyme which conve one of the cytosine bases (in the mRNA) to uracil conveing the codon CAA to UAA (stop codon). Later during translation of this mRNA protein synthesis gets prematurely terminated with final protein missing some of the amino acid of apoB100 protein. This sho version of protein is apoB48. which lacks the hepatic receptor-binding domain (missing amino acids). It has different propeies than apoB100.