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1.  Chromosome abnormalities in pupils attending ESN/M schools. 
Archives of Disease in Childhood  1986;61(3):223-226.
One hundred and sixty six children attending educationally subnormal/mild (ESN/M) schools were karyotyped as part of a project investigating the aetiology of mild mental retardation. Nine had significant chromosome abnormalities. Five of six children identified during the survey had no dysmorphic features--47,XXY (two), 48,XXYY, 46,XX 15q-, and 46,XX,t(X;19). One dysmorphic boy had a balanced translocation--46,XY,t(3;15). Three were already known--47,XX+21 (two) and 46,XY, 14q+. We suggest that routine karyotyping of children with mild mental retardation be considered.
PMCID: PMC1777694  PMID: 2421647
2.  The prevalence of translocations in parents of children with regular trisomy 21: a possible interchromosomal effect? 
Journal of Medical Genetics  1985;22(1):24-28.
It has been suggested that translocations, and perhaps other chromosome rearrangements, disturb meiotic disjunction of uninvolved chromosome pairs and predispose to trisomic offspring. If so, then one would expect an excess of translocations not involving chromosome 21 among the parents of regular trisomic Down's syndrome patients. Such translocations have been reported, but mostly as anecdotal single case reports or very small series. In an attempt to collect a larger series, a collaborative study of regular Down's syndrome families was made in southern England. This was retrospective, and covered periods of 7 to 10 years since 1970. The number of regular trisomy families investigated was 1454. Only 945 of the 2908 parents were karyotyped, and 10 balanced reciprocal translocations not involving chromosome 21 were identified, together with one Robertsonian (13q14q). Expressing these as percentages of the parents tested (945), prevalences are as follows: reciprocals 1.06%, Robertsonians 0.11%, and all translocations 1.16%. Expressed as percentages of the total parents (2908), tested and untested, the prevalences are 0.34%, 0.03%, and 0.37% respectively. The 'true' prevalences, that is what would have been found had all parents been tested, must lie between these two sets of figures. The prevalence of reciprocal translocations exceeds that found for consecutive banded newborn infants, which is 0.16%, and this excess may reflect a real interchromosomal effect. Robertsonian translocations in the banded newborn series are at a frequency of 0.11%, identical to that found in the tested parents of regular trisomics. Interpretation of these figures is critically dependent upon the real prevalence of translocations among the newborn, estimates of which increase as technical methods are improving.
PMCID: PMC1049372  PMID: 3156995
3.  Paracentric inversions in man. 
Journal of Medical Genetics  1984;21(6):407-412.
We have reviewed 50 cases of paracentric inversions. Of these 34 were familial with 62 phenotypically normal carrier relatives. Twenty of the 50 were discovered fortuitously. There were two reports of children with easily recognised unbalanced karyotypes resulting from a paracentric inversion in one of the parents. The vast majority of paracentric inversions are harmless. The risk of abnormal children for paracentric inversion heterozygotes is low but increases with the finding of recurrent abortions or abnormal children or both in other carriers in the family. We emphasise the need for caution in interpreting the results of antenatal diagnosis because of the variety of unexpected unbalanced chromosome types that can result from a paracentric inversion, and the difficulty in recognising, with confidence, minute differences (for the detection of which very high resolution banding is required) between apparently similar parental and fetal inversions.
PMCID: PMC1049338  PMID: 6392555
5.  A familial polymorphic variant of chromosome 5. 
Journal of Medical Genetics  1980;17(6):444-446.
Two male fetuses and their mothers, referred for amniocentesis because of high levels of AFP in their blood, were found to carry an anomalous chromosome 5 with a large heterochromatic segment in the long arm. One of the fetuses had an additional ring chromosome.
PMCID: PMC1885919  PMID: 6162934
8.  Pericentric inversion (13) with two different recombinants in the same family. 
Journal of Medical Genetics  1980;17(4):309-312.
A family is described in which a pericentric inversion (13) was discovered in the father after the birth of an abnormal baby. In a further pregnancy amniocentesis was carried out. The fetal karyotype showed a rec(13)dup p,inv(13)(p11q22). The fetus's abnormalities were similar to those observed in the first child. Family studies showed that a first cousin, mentally retarded, had a rec(13)dup q,inv(13)(p11q22) karyotype. In this family, the risk of occurrence of a recombinant in offspring of an inversion carrier could be as high as 40%.
PMCID: PMC1048576  PMID: 7205907

Results 1-9 (9)