Figure 3.

Proposed secondary-structure models of the new sequence variations in LAMA2 genes. (a) The c.3174+22_23insAT in intron 22 of the LAMA2 gene was predicted not to affect RNA secondary structure. (b) Position of the c.6085delA in LAMA2. The deletion is situated at position +12 in the 5' consensus splice site of intron 42. The c.6085delA is underlined. Position +1 indicates the first nucleotide of the 5' splice site of exon 42. (c) Comparison of RNA secondary structure of [exon 42 + intron 42 + exon 43] between the original sequence and the c.6085+12delA bearing sequence. Several structural changes were predicted. The arrows indicate modifications in folding. (d) Detailed RNA structure analysis of the 5' splicing consensus. The original sequence contained an external closing pair between G¹²C²¹ with a hairpin loop between the G¹³ and C²⁰ positions containing an A at position 6085. The c.6085+12delA deletion shifts the 8 bp external hairpin loop and induced a change in its nucleotide composition. Moreover, orientation of the external loop was modified.