The inversions are one of the most common chromosomal abnormalities. They occur when two breaks occur in a
chromosome; the segment as well originated is reversed and becomes the reintegration on the same chromosome.
Generally, an inversion does not cause an abnormal phenotype in the carrier, but it can do so in their offspring. Which
sometimes can be associated with cases of mental retardation, congenital malformations or infertility. It is critical to
determine if the inversion has a family origin, where there usually is no risks for the individual, or if it is a de novo
mutation, the risk is somewhat higher, possibly due to the interruption of a key sequence of the gene. The pericentric
inversion of chromosome 1 is one of the structural chromosomal variations that are not common, and it has been
observed in general population and patients with abnormal phenotypes and disease. We report the case of a child
that came to the office for presenting a failure to thrive every year; the cytogenetic testing reported an inversion of
chromosome 1 without maternal origin nor paternal. In this case, there is no evidence that low height has relation with
the abnormal chromosome.
Familial pericentric inversion of chromosome 1 (p34q23) and male infertility with stage specific spermatogenic arrest.
