Robertsonian Translocations

Abstract Robertsonian translocations are among the most common balanced structural rearrangements seen in the general population, with a frequency in newborn surveys of about 1 in 1,000. Robertsonian translocations have their own peculiar characteristics and need to be considered separately. These translocations arise from fusions between different acrocentric chromosomes (heterologous Robertsonian translocation) or, rather rarely, between the same chromosome (homologous Robertsonian translocation). The imbalances which may be seen in gametes/offspring of carriers are either pure aneuploidies, or full uniparental disomies. There is also an association with male infertility. This chapter considers the case of the phenotypically normal person who carries, in balanced form, a Robertsonian translocation.