Down syndrome is the most common autosomal chromosome anomaly with several medical abnormalities and intellectual disability, occurring in about of 1:1,000 to
1:1,100 infants. Many pregnancies in women with Down syndrome produce children
both with normal and with trisomy 21, whereas males are infertile. However, Down
syndrome males are not always infertile and this is not global. Here we reported
a 36-year-old man with proved nonmosaic trisomy 21 fathered two normal boys.
Paternity analysis using 26 microsatellite loci confirmed that Down syndrome male is
the biological father of his two normal boys. Serum LH, FSH, testosterone and 17-OH
progesterone were all in the normal range in this father with Down syndrome. To the
best of our knowledge, this is the second report of one man with Down syndrome
who has two normal children in the world. The current study not only supports the
rare evidence of the fertility of males with Down syndrome but also highlights the
caution in advising people responsible for the care of adults with this condition about
possible fertility and transmission of sexual diseases as well