FMR1 and fragile X syndrome: A second study used organoids from iPSCs that were CRISPR/Cas9 gene edited to knockout FMRP (FMR1-KO) and found that FMR1 KO leads to overall bigger organoids from 50 to 100 days in culture which resembles the macrocephaly phenotype that has been reported in FXS patients [121].