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.
They are receptors that are activated by the hormone estrogen (17Î²-estradiol). Two classes of estrogen receptor exist: ER, which is a member of the nuclear hormone family of intracellular receptors, and GPER (GPR30), which is a member of the rhodopsin-like family of G protein-coupled receptors. This article refers to the former (ER). Once activated by estrogen, the ER is able to translocate into the nucleus and bind to DNA to regulate the activity of different genes (i.e. it is a DNA-binding transcription factor). However, it also has additional functions independent of DNA binding.