Unraveling uniparental disomy
Normally, every human has 22 pairs of chromosomes (called homologous chromosomes or homologs or autosomes) plus one couple of sexual chromosomes (which are two X chromosomes in females and one chromosome X plus one chromosome Y in males). For normal development, we need that, for each pair of autosomes, one is inherited from the mother […]Continue reading
Robertsonian translocations: what to do?
A Robertsonian translocation is a chromosomal rearrangment involving two acrocentric chromosomes. Robertsonian translocations are actually the most frequent chromosomal rearrangment in humans, showing an incidence of 1 in 1,000. A difference between Robertsonian translocations and balanced translocations is in that people with a Robertsonian translocation has 45 chromosomes instead of 46. The translocation takes place […]Continue reading
Balanced translocations: what to do?
A balanced reciprocal translocation consists of reciprocal material exchange between two non-homologous chromosomes. Usually, balanced reciprocal translocations can be diagnosed by karyotype analysis (an example of translocation name within a karyotype report could be: 46,XX,t(12:18)(p12;q12.3), which stays for female karyotype with an apparently balanced translocation between chromosomes 12 and 18, which exchanged the region p12 […]Continue reading