The main stem of the Bay itself is about 189 miles (304 km) long, from the Susquehanna River in the north to the Atlantic Ocean in the south. At its narrowest point near Annapolis, Maryland, the Bay is 4 miles (6.4 km) wide; at its widest point, near the mouth of the Potomac River, it is 30 miles (50 km) wide.
Patau syndrome. Patau syndrome is a syndrome caused by a chromosomal abnormality, in which some or all of the cells of the body contain extra genetic material from chromosome 13. The extra genetic material disrupts normal development, causing multiple and complex organ defects.
Rare genetic mutation confirmed as a cause of Tourette Syndrome. Brain researchers say they have confirmed for the first time that a rare genetic mutation can cause some cases of Tourette syndrome, with the fault disrupting production of histamine in the brain. Tics are repetitive movements and vocal sounds, and they are unwanted and involuntary - they cannot be controlled.