Bartsocas-Papas Syndrome 1, also known as popliteal pterygium syndrome, lethal type, is related to bartsocas-papas syndrome and bartsocas-papas syndrome 2. An important gene associated with Bartsocas-Papas Syndrome 1 is RIPK4 (Receptor Interacting Serine/Threonine Kinase 4). Affiliated tissues include skin and uterus, and related phenotypes are microphthalmia and hypoplasia of the maxilla