Protein sequence analysis shows amino acid F153 is completely conserved among β‑integrin subunits. Sequence alignment of partial amino acid sequence of ITGB3 (βI-domain, β2-strand) from various species (ortholog alignment) and from various human β-subunits (paralog alignment) indicates that phenylalanine (F)153 mature β3-subunit (amino acid number is 179 including propeptide sequence) is 100% conserved among species and in all human integrin β-subunits.