Broad palm with single palm crease is visible in a person suffering from-

Down's syndrome:

• This happens due to non-disjunction of chromosomes.
• This is a trisomy of 21st chromosome (autosomal).
• Individuals with Down syndrome are mentally retarded.
• They have a characteristic broad face with a flat nasal bridge, wide-set eyes, and prominent epicanthic folds.
• The hands are also broad with a single crease in the palm.