*4.8. Protein Expression Level from Databases*

The expression of ABCA genes at the protein level was analyzed in the Human Protein Atlas (Consortium Project; http://www.proteinatlas.org) and Expression Atlas (EMBL-EBI; https://www.ebi. ac.uk/gxa/home). The expression of ABCA genes was tested in 45 and 31 normal human tissues in the Human Protein Atlas and Expression Atlas, respectively. The two variables reflecting the overall distribution and expression in human tissues and their following levels were collected: (A) Protein tissue distribution: 1-One tissue/2-Some tissues (less than a half of the tissues studied in the atlases)/3-Many tissues (equal to or greater than half of the tissues)/4-All tissues, and (B) Mode expression score (the most common level of protein expression based on immunohistochemistry scoring): 1-Not detected/2-Low/3-Medium/4-High. The mode expression score was calculated for the set of tissues where protein expression was detected.
