In this unit, CDK19 is combined with Cyclin C, MED12L, and MED13L.1 In 2020, it was first evidenced that de novo heterozygous missense variants in CDK19 cause a new neurodevelopmental disorder, so the disease became known as Developmental and Epileptic Encephalopathy 87 (DEE87; MIM #618916) [96], placing it among the MEDopathies [95]. Here, MED12L is linked to developmental and epileptic encephalopathy, 87.