• middle of the chromosome
  • Before this happens, every chromosome is copied once (S phase), and the copy is joined to the original by a centromere, resulting either in an X-shaped structure (pictured to the right) if the centromere is located in the middle of the chromosome or a two-arm structure if the centromere is located near one of the ends. (wikipedia.org)
  • translocations
  • CMA does not detect balanced chromosome rearrangements in which there is no gain or loss of DNA (balanced inversions or balanced translocations). (unicare.com)
  • CMA is more sensitive than karyotyping, which cannot identify submicroscopic abnormalities such as translocations, deletion or duplications. (unicare.com)
  • sickle-cell a
  • PGD became increasingly popular during the 1990s when it was used to determine a handful of severe genetic disorders, such as sickle-cell anemia, Tay Sachs disease, Duchenne's muscular dystrophy, and beta-thalassemia. (wikipedia.org)
  • intellectual
  • Babies with trisomy 13 have three copies of chromosome 13 and have severe intellectual disabilities. (lifelabs.com)
  • In addition to retinoblastoma, deletions of the 13q14 region may cause intellectual disability, slow growth, and characteristic facial features such as prominent eyebrows, a broad nasal bridge, a short nose, and ear abnormalities. (nih.gov)
  • This document addresses chromosomal microarray analysis (CMA) as a diagnostic tool for congenital anomalies as well as for individuals with unexplained developmental delay (DD), autism spectrum disorder (ASD) or intellectual disability (intellectual developmental delay). (unicare.com)
  • Major characteristics for this disorder are intellectual disability, muscle weakness and lack of coordination. (wikipedia.org)
  • karyotype
  • Chromosome 1 may contain a gene responsible for tumor development and lead to changes in the karyotype, including fusion of the centromere, or centric fusions. (wikipedia.org)
  • Sperm
  • The old adage "we are what we eat" received further support this week, and may even suggest "we are what our parents ate" when a new study by researchers in the US revealed that healthy men who have a diet low in folate have a higher risk of chromosomal abnormalities in their sperm. (babyafter40.com)
  • Young said their study was the first to examine the effects of diet on chromosomal abnormalities in sperm. (babyafter40.com)
  • symptoms
  • Symptoms of the disorder are comparable to those of trisomy 9p. (wikipedia.org)
  • The severity of the symptoms is largely determined by the size of the isochromosome, the specific regions of chromosome 9p that are duplicated, as well as the number and type of tissues that are affected in the mosaic form. (wikipedia.org)
  • This provides evidence that it is the number of RAI1 copies present that affects the symptoms of PTLS and SMS. (wikipedia.org)