- De novo 46,XX,t(6;7)(q27;q11;23) associated with severe cardiovascular manifestations characteristic of supravalvular aortic stenosis and Williams syndrome. von Dadelszen, P., Chitayat, D., Winsor, E.J., Cohen, H., MacDonald, C., Taylor, G., Rose, T., Hornberger, L.K. Am. J. Med. Genet. (2000)