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1.  Use of overlapping normal distributions in genetic counselling. 
Journal of Medical Genetics  1978;15(2):106-108.
If a numerical variable can be assumed to be normally, but differently, distributed in each of two or more populations, then for an 'unknown' individual whose numerical value is known the relative probability of his belonging to each of the populations can be simply calculated. We briefly review the method and its application in genetic counselling.
PMCID: PMC1013655  PMID: 641941
3.  Three patients with ring (X) chromosomes and a severe phenotype. 
Journal of Medical Genetics  1993;30(6):482-486.
Three patients with mosaicism and a cell line containing a small ring (X) chromosome are described. Their phenotype is similar to several previously reported patients with a 45,X/46,X,r(X) karyotype and a phenotype far more severely affected than expected in Turner's syndrome. The clinical picture includes mental retardation, a facial appearance reminiscent of the Kabuki make up syndrome, and limb anomalies. Some of the patients also had streaky hyperpigmentation of the skin in a pattern suggesting dermal mosaicism. It has been hypothesised that the severe phenotype might be the result of the small r(X) chromosome remaining active. However, there is little critical evidence to support this suggestion, while there is considerable evidence against it, including (1) a similar phenotype in 45,X/46,X,r(Y) patients, (2) the late replication of some of the small r(X) chromosomes associated with this phenotype, and (3) the expression of XIST in some of the affected patients.
PMCID: PMC1016421  PMID: 8326492
4.  Williams-Beuren syndrome: phenotypic variability and deletions of chromosomes 7, 11, and 22 in a series of 52 patients. 
Journal of Medical Genetics  1996;33(12):986-992.
Fluorescence in situ hybridisation (FISH) and conventional chromosome analysis were performed on a series of 52 patients with classical Williams-Beuren syndrome (WBS), suspected WBS, or supravalvular aortic stenosis (SVAS). In the classical WBS group, 22/23 (96%) had a submicroscopic deletion of the elastin locus on chromosome 7, but the remaining patient had a unique interstitial deletion of chromosome 11 (del(11)(q13.5q14.2)). In the suspected WBS group 2/22 (9%) patients had elastin deletions but a third patient had a complex karyotype including a ring chromosome 22 with a deletion of the long arm (r(22)(p11-->q13)). In the SVAS group, 1/7 (14%) had an elastin gene deletion, despite having normal development and minimal signs of WBS. Overall, some patients with submicroscopic elastin deletions have fewer features of Williams-Beuren syndrome than those with other cytogenetic abnormalities. These results, therefore, emphasise the importance of a combined conventional and molecular cytogenetic approach to diagnosis and suggest that the degree to which submicroscopic deletions of chromosome 7 extend beyond the elastin locus may explain some of the phenotypic variability found in Williams-Beuren syndrome.
PMCID: PMC1050807  PMID: 9004128
5.  A comparison of the clinical and cytogenetic findings in nine patients with a ring (X) cell line and 16 45,X patients. 
Journal of Medical Genetics  1994;31(7):528-533.
In this study, the clinical, IQ, and cytogenetic findings in nine Turner's syndrome patients with a ring (X) cell line are compared with those in 16 patients in whom only a 45,X cell line could be found. The ring (X) patients lacked many of the "classic" Turner's syndrome features and the majority were not karyotyped until after the age of 11, usually because of pubertal failure. They also showed a reduction in IQ of 11 points compared with the 45,X group. Some ring (X) patients show characteristic facial features including a broad nose with anteverted nostrils, prominent philtrum, long palpebral fissures, and a wide mouth with a thin upper lip. Neither the physical features nor the IQ are related to the parental origin of the chromosome error. In the majority of cases the ring (X) chromosome was late replicating but XIST activity is being studied further.
PMCID: PMC1049974  PMID: 7966189
7.  Population studies of the fragile X: a molecular approach. 
Journal of Medical Genetics  1993;30(6):454-459.
The fragile X mutation can now be recognised by a variety of molecular techniques. We report a pilot screening survey of a population of children with mental impairment in which we used Southern blotting methods to detect the fragile X mutation, augmented by cytogenetic studies on children whose phenotype suggested a possible chromosome abnormality. There were 873 children with special educational needs in our survey and 310 fulfilled our criteria for testing. A sample was obtained from 254, of whom four were found to have a full fra(X) mutation (delta L) and none to have a premutation. The number of CGG repeats in our population of X chromosomes was measured by PCR analysis and the genotype at the closely linked polymorphic locus FRAXAC1 established. The distribution of CGG repeat numbers was very similar to that of the control population reported by Fu et al and the distribution of FRAXAC1 alleles almost identical to that of the control population reported by Richards et al. Among the non-fragile X chromosomes, we found a very significant correlation between the size of the CGG repeat and the FRAXAC1 genotype. There was a dearth of A and D genotypes in subjects with a small number of CGG repeats and an excess of the A genotype in those with a large number of CGG repeats. These observations are considered in the light of the reported disequilibrium between the A (and possibly also the D) genotype and the fra(X) mutation.
PMCID: PMC1016415  PMID: 8326487
8.  A non-isotopic in situ hybridisation study of the chromosomal origin of 15 supernumerary marker chromosomes in man. 
Journal of Medical Genetics  1992;29(10):699-703.
Fifteen patients presenting with mosaic or non-mosaic karyotypes containing a distamycin-DAPI negative de novo or familial supernumerary marker chromosome were studied with non-isotopic in situ hybridisation using a library of alphoid centromere specific and satellite II/III probes. The in situ hybridisation studies showed that seven markers were derived from satellited autosomes (three chromosome 13/21, two chromosome 14, two chromosome 22), six from non-satellited autosomes (two chromosome 4, one chromosome 12, one chromosome 16, two chromosome 19), and one from the Y chromosome. One non-mosaic marker was negative for all the alphoid and satellite II/III probes used.
PMCID: PMC1016126  PMID: 1433228
9.  Weaver syndrome. 
Journal of Medical Genetics  1992;29(5):332-337.
PMCID: PMC1015954  PMID: 1583661
10.  Deletion Xp22.3. 
Journal of Medical Genetics  1990;27(9):598.
PMCID: PMC1017228  PMID: 2231657
12.  Two 46,XX,t(X;Y) females with linear skin defects and congenital microphthalmia: a new syndrome at Xp22.3. 
Journal of Medical Genetics  1990;27(1):59-63.
We describe two females with de novo X;Y translocations, who presented at birth with irregular linear areas of erythematous skin hypoplasia involving the head and neck, along with eye findings that included microphthalmia, corneal opacities, and orbital cysts. The features in these children are similar to but distinct from those seen in females with Goltz syndrome and incontinentia pigmenti. Cytogenetic analysis has shown the X chromosome breakpoint in both females to be at Xp22.3. We suggest that this syndrome is the result of a deletion or disruption of DNA sequences in the region of Xp22.3.
PMCID: PMC1016884  PMID: 2308157
15.  Interstitial deletion of distal 13q associated with Hirschsprung's disease. 
Journal of Medical Genetics  1989;26(2):100-104.
Three cases of interstitial deletion of chromosome 13 involving the common segment 13q22.1----q32.1 are reported. In addition to the recognised clinical features of this deletion, two had Hirschsprung's disease.
PMCID: PMC1015558  PMID: 2918536
21.  Use of creatine kinase for detecting severe X-linked muscular dystrophy carriers. 
British Medical Journal  1976;2(6035):577-579.
Women thought to be at risk of being carriers of Duchenne muscular dystrophy were given "odds" against their having an affected child. These were calcuated from a combination of the genetic risk from the family history and an estimation of the biochemical risk from measuring the serum creatine kinase concentration. The women were told the actual risk estimate and it was put into perspective for them as a high, medium, or low risk. Of 25 women at high risk six have had children, all girls; the two in the medium-risk group have had no children; and the 46 women at low risk have had 19 boys and 25 girls. None of the boys has the disease. With detailed counselling most potential carriers of this disease reach decisions in child bearing that are in line with their degree of risk.
PMCID: PMC1688064  PMID: 963439
22.  Letter: Cleft lip and palate. 
British Medical Journal  1974;3(5928):469.
PMCID: PMC1611465  PMID: 4414146
23.  Duplication of 8p23.1: a cytogenetic anomaly with no established clinical significance. 
Journal of Medical Genetics  1998;35(6):491-496.
We present seven families with a cytogenetic duplication of the short arm of chromosome 8 at band 8p23.1. The duplication has been transmitted from parents to offspring in four of the seven families. In three families, the source of the extra material and its euchromatic origin were established using FISH with a YAC which was mapped to 8p23.1 and a whole chromosome paint for chromosome 8. FISH signals from this YAC were significantly larger on the duplicated chromosome compared with the normal chromosome in all six family members tested. Comparative genomic hybridisation (CGH) on a representative subject was consistent with these results. The families were ascertained for a variety of mostly incidental reasons including prenatal diagnosis for advanced maternal age. The transmission of this duplication by multiple phenotypically normal family members with no history of reproductive loss suggests the existence of a novel class of 8p23.1 duplications, which can be regarded as euchromatic variants or duplications with no phenotypic effect.
PMCID: PMC1051344  PMID: 9643291
24.  Holoprosencephaly: a family showing dominant inheritance and variable expression. 
Journal of Medical Genetics  1993;30(1):36-40.
A family with probable dominant holoprosencephaly is presented with five affected subjects in two sibships, the offspring of healthy sisters who are presumed gene carriers. Of the affected children, three had cebocephaly and died shortly after birth. One had left choanal atresia, retinal coloboma, a single central maxillary incisor, microcephaly, short stature, and learning problems. Another had only a single central maxillary incisor. The occurrence of hypotelorism, microcephaly, and unilateral cleft lip and palate as minor manifestations of the gene in possible and probable gene carriers is discussed.
PMCID: PMC1016231  PMID: 8423605
25.  Familial Ebstein's anomaly: a report of six cases in two generations associated with mild skeletal abnormalities. 
British Heart Journal  1991;66(1):26-28.
In a family of 11 persons in three generations six had Ebstein's anomaly. Five of the six showed mild skeletal anomalies--that is, restricted finger extension, with or without limitation of larger joints, and externally rotated little toes. Two other members of the family had the skeletal features without Ebstein's anomaly. The findings suggest a dominantly inherited syndrome of Ebstein's anomaly and skeletal abnormalities. The four female patients were all mildly affected whereas three of the four male patients were severely affected.
PMCID: PMC1024561  PMID: 1854572

Results 1-25 (29)