Best Answer: Chordata refers to the presence of a nerve chord running from the head to the back, which may or may not be accompanied by vertebrae. All animals with backbones are members of the chordate phylum, but not all chordates have bones (lancelets and tunicates are chordates lacking real bones).
Angelman syndrome is a complex genetic disorder that primarily affects the nervous system. Characteristic features of this condition include delayed development, intellectual disability, severe speech impairment, and problems with movement and balance (ataxia).n some people who have Angelman syndrome, the loss of a gene called OCA2 is associated with light-colored hair and fair skin. The OCA2 gene is located on the segment of chromosome 15 that is often deleted in people with this disorder.
Improper imprinting can result in an individual having two active copies or two inactive copies. This can lead to severe developmental abnormalities, cancer, and other problems. Prader-Willi and Angelman syndrome are two very different disorders, but they are both linked to the same imprinted region of chromosome 15. Some of the genes in this region are silenced in the egg, and at least one gene is silenced in the sperm.