*2.14. Descriptive Statistics Shows High Abundance and Great Variability of 5*′*UTR Features*

Among the 12 ABCA genes, the minimum 5′UTR length is 26 nts (*ABCA13*), maximum length 910 (*ABCA10*) and mean/average (M) 291 (median (Mdn) 212 and mode (Mo) 97). The minimum number of uATGs is 0 (*ABCA5* and *ABCA13*), maximum 14 (*ABCA10*) and M = 3 (Mdn = 2 and Mo = 1). The minimum number of uORFs is 0 (*ABCA4*, *ABCA5*, *ABCA6*, and *ABCA13*), maximum 6 (*ABCA10*) and M = 1 (Mdn = 1 and Mo = 1). The minimum number of 5′UTR introns is 0 (*ABCA2, ABCA4*, *ABCA12*, and *ABCA13*), maximum 3 (*ABCA3* and *ABCA10*) and M = 1 (Mdn = 1 and Mo = 1). The minimum 5′UTR intron length is 890 nts, maximum 24,163 and M = 7208 (Mdn = 5746 and Mo not applicable). Only four genes have one RG4 each (*ABCA1*, *ABCA2*, *ABCA3*, and *ABCA7*). The minimum number of 5′UTR stem loops is 0 (*ABCA13*), maximum 6 (*ABCA1* and *ABCA12*) and M = 3 (Mdn = 3 and Mo = 2). The minimum number of all 5′UTR elements is 0 (*ABCA13*), maximum 22 (*ABCA10*) and M = 8 (Mdn = 6 and Mo = 6). Table 2 presents the summary of the 5′UTRs' descriptive statistics.


**Table 2.** Descriptive statistics of the 5′UTR features in human ABCA genes.

No., number; RG4, RNA G-quadruplex; uATG, upstream ATG; uORF, upstream ORF.
