P5 additionally presented progressive, juvenile onset dystonia with predominant cranio-cervical involvement and was finally diagnosed with KMT2B-related childhood onset dystonia (Dystonia 28; DYT28) by identification of the novel de-novo c.5697del (p.Thr1900Glnfs*34) KMT2B variant. This evidence concerns the gene KMT2B and Developmental malformations - deafness - dystonia.