The most common cause of Angelman syndrome is a deletion of the maternal chromosome region 15q11-q13, which includes the UBE3A gene. Importantly, mutations and deletions of the UBE3A gene are sufficient to cause Angelman syndrome, making UBE3A the single gene responsible for the core symptoms of the disorder. Two major deletion classes known as class I and class II deletions in the 15q11-q13 region both cause Angelman syndrome.
1 ER+/PR+: About 65% of estrogen-receptor-positive breast cancers are also progesterone-receptor-positive. 2  This means that the cells have receptors for both hormones, which could be supporting the growth of the breast cancer.
1 Once inside a target cell, the hormone (pink) binds to a receptor (purple) - similar to a hand sliding in a glove or mitten-and forms what is known as a hormone-receptor complex between the ligand and receptor.2  A ligand is any molecule that binds to a specific site on a protein or other molecule. In this case, the estrogen hormone 17-beta-estradiol is the ligand, and the estrogen receptor is the protein. 2  Binding turns on, or activates, a hormone receptor. 3  Activation sets in motion cell signaling systems that trigger gene expression and lead to responses typical of a particular hormone.