<prompt> Most common cardio vascular abnormality in dow n syndrome is-YSDEndocardial cushion defectTOFCOA  <response>: Ans. is b i.e., Endocardial cushion defect o About 40 of down syndrome have CHD.Endocardial cusion A trio ventricular septal defect account for 40-60 of cases.Other feature in down syndrome.Hypotonia, flat face, upward and slanted palpebral fissures and epicanthic folds, speckled irises Brushfield spot;varving degrees of mental and growth retardation;dvsplasia of the pelvis, cardiac malformations, and simian crease; short, broad hands, hypoplasia of middle phalanx of 5th finger, duodenal atresia, and high arched palate ;5 of patients with Down syndrome are the result of a translocation-t 14q2 lq, t 15q2 lq, and t 13q21 q-in which the phenotype is the same as trisomy 21.Other feature -Duodenal atresiaAnnular pancreasTracheoesophageal fistulaHirschsprung diseaseShort statureShort sternumBrachvcephalvDelayed fontanel closureThree fontanelsFrontal sinus hypoplasiaPeripheral joint laxityAtlantoaxial instability C1-C2 subluxationExaggerated space betweenMottled skin in infancy13 Dry coarse skin in adolescence 1st and 2nd toesIncreased Risk for Development of -Leukemia:AML, ALLMyelodysplasiaTransient lymphoproliferative syndromeCeliac disease a Hypothyroidism a Diabetes mellitus a ObesityRefractive errorsStrabismusMitral valve prolapseConductive andorObstructive sleep apneaEpilepsy sensorineural hearing loss a ADHD Alzheimer diseaseConduct oppositional disorders 