Supplementary Methods

Recombinant His-tagged SSB
The recombinant His-tagged SSB was custom-made (cloned, overexpressed and purified) by PROTEIN EXPERT, Grenoble, France. Its sequence is as follow: “MASRGVNKVILVGNLGQDPEVRYMPNGGAVANITLATSESWRDKATGEMKEQTEWHRVVLFGKLAEVASEYLRKGSQVYIEGQLRTRKWTDQSGQDRYTTEVVVNVGGTMQMLGGRQGGGAPAGGNIGGGQPQSGWGQPQQPQGGNQFSGGAQSRPQQSAPAAPSNEPPMDFDDDIPFHHHHHHHH”
It corresponds to the native single-stranded DNA-binding protein (SSB) of Escherichia coli (Meyer and Laine 1990; GenBank accession no. J01704) equipped at its C-terminal end with an additional tag of 8 histidine residues (in bold characters).

RT-PCR validation of the two new AS events identified within the P4HA2 and GSTP1 genes 
Reverse transcription (RT) was performed using one µg of total RNA from human placenta, random hexamer primers and SuperScript II following manufacturer instruction (Invitrogen). One ten of the RT was used in a PCR reaction using manufacturer instruction (Invitrogen). The primers used for the PCR reactions were as follow:
P4HA2S1 : (5’)GGAAGCTGCGAGTGTCCAG(3’)
P4HA2S2 : (5’)GGAGACCCGTGATAATTCG (3’)
P4HA2AS : (5’)GCACCAGCTCTTTCTCTGC(3’)
GSTP1S1 : (5’)TCTATGGGAAGGACCAGCAG(3’)
GSTP1S2 : (5’)TTCATTGTGGGAGACCAGGTG (3’)
GSTP1AS :   (5’)GCTAGGACCTCATGGATCAG(3’)