Cytogenetics of Down’s Syndrome (Mongolism) III. Frequency of Interchange Trisomics and Mutation Rate of Chromosome Interchanges

Polani, P. E.; Hamerton, J.L.; Giannelli, F.; Carter, C.O.

doi:10.1159/000129855

Cited by 38 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The finding o f five sporadic and one inherited interchange trisomics in 92 cases o f D ow n's syndrome, born at maternal ages o f less than 30, is entirely consistent with the findings in other series (Sergo v ic h et a l., 1964; G ia n n e l l i et a l., 1965) . These observations are discussed in the following two papers, both in relation to their relevance to genetic counselling (G ia n n e l l i et a l., 1965) and in relation to chromosome mutation rate (Polani et a !., 1965).…”

Section: Discussionmentioning

confidence: 99%

Cytogenetics of Down’s Syndrome (Mongolism) I. Data on a Consecutive Series of Patients Referred for Genetic Counselling and Diagnosis

Hamerton¹,

Giannelli²,

Polani³

1965

Cytogenet Genome Res

Self Cite

View full text Add to dashboard Cite

The chromosome findings in a series of 173 Down’s syndrome or presumptive Down’s syndrome index patients, and a further 3 5 pairs of parents of Down’s syndrome index cases, are given. One hundred and forty-four index cases had primary G₂₁ trisomy; six were interchange trisomics, six were mosaics, and one was a chromatin positive male with XXY sex chromosomes and primary G₂₁ trisomy. Sixteen index patients whose diagnosis could not be clinically confirmed, were found to have normal chromosomes. The 35 pairs of parents all had normal chromosomes. In seven families (three index patients with primary G₂₁ trisomy, two with normal chromosomes and two index patients not studied) minor morphological chromosome anomalies were observed. The relevance of this data to the causal association of Down’s syndrome and G₂₁ trisomy, the frequency of mosaicism, double trisomy and association with other chromosome anomalies, is discussed.

show abstract

Section: Discussionmentioning

confidence: 99%

Cytogenetics of Down’s Syndrome (Mongolism) I. Data on a Consecutive Series of Patients Referred for Genetic Counselling and Diagnosis

Hamerton¹,

Giannelli²,

Polani³

1965

Cytogenet Genome Res

Self Cite

View full text Add to dashboard Cite

show abstract

“…and the duplication in 17p12 that causes Charcot-Marie-Tooth disease, type 1A (CMT1A). Mutation rates for Robertsonian translocations (ROB) have been estimated from literature surveys of spontaneous abortions (46) or livebirths (46,90), and population surveys of newborns with translocation-type Down syndrome or Patau syndrome (trisomy 13) (41,42,55,94). Since it was technically impossible to distinguish isochromosomes of chromosome 21 or 13 from ROBs, the proportion of de novo rearrangements resulting from isochromosomes was unknown at the time these mutation rates were calculated.…”

Section: Mutation Rates and De Novo Occurrencementioning

confidence: 99%

Molecular Mechanisms for Constitutional Chromosomal Rearrangements in Humans

2000

View full text Add to dashboard Cite

Cytogenetic imbalance in the newborn is a frequent cause of mental retardation and birth defects. Although aneuploidy accounts for the majority of imbalance, structural aberrations contribute to a significant fraction of recognized chromosomal anomalies. This review describes the major classes of constitutional, structural cytogenetic abnormalities and recent studies that explore the molecular mechanisms that bring about their de novo occurrence. Genomic features flanking the sites of recombination may result in susceptibility to chromosomal rearrangement. One such substrate for recombination is low-copy region-specific repeats. The identification of genome architectural features conferring susceptibility to rearrangements has been accomplished using methods that enable investigation of regions of the genome that are too small to be visualized by traditional cytogenetics and too large to be resolved by conventional gel electrophoresis. These investigations resulted in the identification of previously unrecognized structural cytogenetic anomalies, which are associated with genetic syndromes and allowed for the molecular basis of some chromosomal rearrangements to be delineated.

show abstract

“…There is no reliable inforniation about the mutation rate for centric fusion in nature. In nian the interchange mutation rate per chroniosonie 21, per gamete and per generation has been estimated as 2.71 X 10-5-2.07X (POLANI et al, 1965). As mentioned earlier, cytological conditions suggest that the fusion of these particular chromosomes in cattle does not occur in a higher frequency than that expected from chance for translocations of that type.…”

Section: Mutcitiorzmentioning

confidence: 92%

Cytogenetics, Distribution and Phenotypic Effects of a Translocation in Swedish Cattle

Gustavsson

2009

Hereditas

157

View full text Add to dashboard Cite

Cytogenetics of Down’s Syndrome (Mongolism) III. Frequency of Interchange Trisomics and Mutation Rate of Chromosome Interchanges

Cited by 38 publications

References 0 publications

Cytogenetics of Down’s Syndrome (Mongolism) I. Data on a Consecutive Series of Patients Referred for Genetic Counselling and Diagnosis

Cytogenetics of Down’s Syndrome (Mongolism) I. Data on a Consecutive Series of Patients Referred for Genetic Counselling and Diagnosis

Molecular Mechanisms for Constitutional Chromosomal Rearrangements in Humans

Cytogenetics, Distribution and Phenotypic Effects of a Translocation in Swedish Cattle

Contact Info

Product

Resources

About