Fig. 3
![Fig. 3](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs13148-019-0784-0/MediaObjects/13148_2019_784_Fig3_HTML.png)
Diagram of the structure of the ABCG1 (NCBI reference sequence: NM_207629.1) and APOE (NCBI Reference Sequence: NM_000041.4) genes. The line represents the gene (left to right: 5′–3′), and solid rectangles represent exons. Because of the long length of the ABCG1 gene and the scale of the image displayed, most of the exons look like a vertical line instead of rectangles. ABCG1, ATP–binding cassette G1 gene; APOE, apolipoprotein E gene