Does " @entity3521 " exist? An analysis of 207 case reports on XXXX with a ring autosome.

@entity1 @entity154 @entity851 @entity600 @entity854 @entity3521
Analysis of 207 case reports on @entity1 with ring autosome showed that: Forty @entity1 , a fifth of the total, had @entity851 together with an otherwise almost-normal appearance, viz. no major @entity600 , no specific deletion syndrome, no or only a few unspecific @entity154 . This phenotype may be regarded as the " @entity3521 ", a term proposed by Cote et al. (1981) since it is independent of what chromosome is involved. @entity851 , the sole major physical @entity854 ", was seen significantly more often among @entity1 with ring of larger chromosomes than among @entity1 with a smaller ring, indicating that the greater the chromosome involved in ring formation, the higher is the probability of severe @entity851 . Larger ring chromosomes showed significantly more often instability than smaller rings, suggesting that there may be a correlation between ring instability and the size of the chromosome involved. @entity851 was present in significantly more @entity1 with a "labile" ring than with a "stable" ring, indicating that a correlation may exist between ring instability and @entity851 . It is suggested that the " @entity3521 " observed in many cases with ring autosome may result from end-to-end fusion of chromosome ends, an event not involving deletion in the genetic sense. It is also suggested that the " @entity3521 " is caused by a continuous generation of secondary aneuploid cells with increased mortality, i.e. structural ring instability which seems to be a function of the size of the chromosome involved. Thus, formation of a ring chromosome in certain cases might be regarded as a "structural mutation", i.e. an alteration in the structure of the genetic material per se, rather than a loss or gain of genetic dosages.
