Abstract In northern European Cochlearia (Brassicaceae), considerable chromosome variation has taken place without corresponding morphological differentiation, resulting in an intricate species complex including two base numbers and several ploidies. Here, we investigate the situation Iceland. The distribution, genetic structure, taxonomy origin of cytotypes (2n = 12 2n 14) present Iceland are ...

Ring chromosomes are rare chromosomal disorders that usually appear to occur de novo. A ring chromosome forms when due to deletion both ends of chromosome fuse with each other. Depending on the amount of chromosomal deletion, the clinical manifestations may be different. So, ring 18 syndrome is characterized by severe mental growth retardation as well as microcephaly, brain and ocular malformat...

Two cases of ring chromosome 11 are reported. Both had mental retardation, microcephaly, and short stature. High resolution G banding in case 1 showed no visible loss of chromatin, the karyotype being assessed as 46,XX,r(11) (p15 X 4q2 X 5). In case 2, a Wilm's tumour developed at 8 months and the child died at 18 months. Cytogenetic analysis by Q banding demonstrated minimal chromosome deletio...

The combination of cytogenetic, biochemical, and family studies for investigation of patients who have partially deleted chromosomes provides a potential opportunity to learn what genes were present on the fragment deleted from the chromosome. In addition, the genes on its remaining homologue can be studied in their hemizygous state. The ring chromosome, an example of a partially deleted chromo...

We present the clinical, electroencephalographic, neuroimaging (brain magnetic resonance image - MRI and spectroscopy by MRI) and cytogenetic findings of a young male patient with a rare cytogenetic anomaly characterised by a de novo 46,XY,r(20)(p13q13.3) karyotype. He presents with mental retardation, emotional liability, and strabismus, without any other significant dysmorphies. There are bra...

During cell division, chromosomes attach to spindle microtubules at sites called kinetochores, and force generated at the kinetochore-microtubule interface is the main driver of chromosome movement. Surprisingly, kinetochores are not required for chromosome segregation on acentrosomal spindles in Caenorhabditis elegans oocytes, but the mechanism driving chromosomes apart in their absence is not...