Endometrial stromal tumours are a type of mesenchymal tumor of the main body of the uterus. Types include endometrial stromal nodule, the distinct low and high-grade endometrial stromal sarcomas, and undifferentiated uterine sarcoma. == References ==
Associated with the hair forelock, skin pigmentation can also appear in different parts of the body and limbs (suspected to be caused by the mutation in KIT). In parts of the body of some patients, congenital leukoderma is observed.Similar to other types of the syndrome, Type 1 displays heterochromia in some patients, sometimes complete or partial. If it happens to be partial, the differently colored iris is separated from the radial segment of the eye. Deficient iris stroma along with hypoplastic blue arises have also been found in some patients with Type 1. Another one of the symptoms is hearing loss, presenting in about 69% of cases. The types of hearing loss reported in patients differ over a great spectrum. Some of which could be bilateral or unilateral, sensorineural sometimes a combination of different ones in each ear. The most common loss types reported for Type 1 are profound and bilateral. Waardenburg Type 1 is estimated to cause 3% of overall congenital deaf children. Genetics
Type 1 Waardenburg Syndrome is a dominant autosomal disease, with extremely high penetrance of nearly 85%  Type 1, as well as type 3, are linked to a mutation in the PAX3 gene located in chromosome 2q35. This gene is responsible for encoding a transaction factor named Drosophila paired (noted as prd) resulting in essential proteins. These proteins are responsible for multiple functions in early human development such as stem cell pluripotency, as well as inhibition of differentiation when needed and cell-lineage specification, migration, and proliferation in the cells .