<prompt> Increased nuchal fold thickness is a feature ofPaulBunnel syndromeDepan syndromeDowns syndromeCriduchat syndrome  <response>: Nuchal fold thickness is increased in Down syndrome. This feature is used in suspecting the diagnosis of Downs syndrome prenataly.Downs syndrome Downs syndrome is due to trisomy 21.Downs syndrome is the most common trisomy.In this condition, extra genetic material causes a delay in the way a child develops and often leads to mental retardation.In Downs syndrome the child gets on the extra chromosome, he has a total of 47 chromosomes instead of 46 chromosomes.This is the extra genetic material that causes the physical and cognitive delays associated with Downs syndrome.There is a well-recognized association with advanced maternal age, the risk considerably increases in women 35 years of age.Advanced paternal age has no effect. 