NR2F1 and Bosch-Boonstra-Schaaf optic atrophy syndrome: The brain MRI results reported in the literature showed that corpus callosum thinning was observed in 8 of 15 BBSOAS patients, all presenting with DD, ID, and optic nerve atrophy (ONA), while DD and ID were observed in 6 of 7 normal corpus callosum patients with BBSOAS, and ONA was observed in 4 of them.[3] Furthermore, Armentano M revealed the important role and mechanism of NR2F1 in the abnormal development of corpus callosum during axon growth in vivo mouse.[18] However, our fetus was lack of corpus callosum thinning which might be related to the small GA.