FGFR1 and arachnoid cyst: In fact, in another case of a newborn who experienced left-sided lesion in the brain, arachnoid cysts, and optic nerve colobomas, the authors performed newborn genetic screening, chromosomal analysis, microarray, FGFR related disorders via the FGFR-1 gene, and a comprehensive brain malformation sequencing panel, which all returned negative [30].