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In accordance with Nielsen & Stradiot's protocol (1987), we report on the long-term follow-up in 50 adult females with Ullrich-Turner syndrome. Attention is drawn mainly to social problems.

Oculo-facio-cardio-dental (OFCD) syndrome is a rare X-linked dominant condition with male lethality characterized by microphthalmia, congenital cataracts, facial dysmorphic features, congenital heart defects, and dental anomalies. Mutations in BCOR (BCL6 co-repressor) located in Xp11.4 have been described to cause OFCD syndrome. Lenz microphthalmia syndrome is inherited in an X-linked recessive pattern comprising microphthalmia/anophthalmia, mental retardation, malformed ears, digital, skeletal, and urogenital anomalies (synonym: microphthalmia with associated anomalies (MAA)). One locus for MAA has been mapped to Xq27-q28. Nonetheless, linkage and subsequent mutation analysis revealed a single missense mutation (p.P85L) in BCOR in a large family with presumed Lenz microphthalmia syndrome (MAA2). We describe novel mutations in BCOR in three patients with OFCD syndrome, two small deletions (c.2488_2489delAG and c.3286delG) and a submicroscopic deletion of about 60 kb encompassing at least BCOR exons 2-15. No BCOR mutation was detected in eight patients with Lenz microphthalmia syndrome. Our data confirm that BCOR is the causative gene for OFCD syndrome; however, the failure to identify any mutation in patients with Lenz microphthalmia syndrome together with the oligosymptomatic phenotype in the reported MAA2 patients suggest that BCOR is not the major gene for this syndrome.

We report clinical, cytogenetic, and molecular cytogenetic studies on four patients with subtle or submicroscopic 7q36 deletions either of de novo origin or resulting from a cryptic parental translocation. Fluorescence in situ hybridization (FISH) studies indicated that in all four patients, the Sonic Hedgehog gene (SHH) and the homeobox gene HLXB9, among others, are comprised in the deletions. Besides mental retardation and short stature, all patients showed only minimal manifestations of the holoprosencephaly (HPE) spectrum and only one displayed symptoms of the Currarino syndrome. Patient 1 had a de novo 7q36.1-qter deletion and showed microcephaly, ptosis, sacral agenesis, tethered cord, but no structural brain anomaly. Patient 2 had a submicroscopic de novo 7q36 deletion detected by FISH, and showed facial and cerebral microsigns of the HPE spectrum. Patient 3 had a 7q36 deletion found by subtelomere FISH testing that was the unbalanced product of a subtle maternal 7q;10q translocation. She presented facial and ocular microsigns, but no structural abnormality of the brain. Patient 4 showed no specific syndromal pattern and was found to have a cryptic unbalanced de novo translocation of the terminal parts of chromosomes 7q and 9p by subtelomere FISH. Patients 2, 3, and 4 represent the first report of a de novo submicroscopic 7q36 deletion, the second report of a familial subtle translocation of 7q36, and the first report of an unbalanced de novo submicroscopic translocation of 7q36, respectively. Our results stress the importance of 7q36 deletion studies by FISH in patients with microsigns of the HPE spectrum.

Noonan syndrome (NS) is a relatively common, but genetically heterogeneous autosomal dominant malformation syndrome. Characteristic features are proportionate short stature, dysmorphic face, and congenital heart defects. Only recently, a gene involved in NS could be identified. It encodes the non-receptor protein tyrosine phosphatase SHP-2, which is an important molecule in several intracellular signal transduction pathways that control diverse developmental processes, most importantly cardiac semilunar valvulogenesis. We have screened this gene for mutations in 96 familial and sporadic, well-characterised NS patients and identified 15 different missense mutations in a total of 32 patients (33%), including 23 index patients. Most changes clustered in one exon which encodes parts of the N-SH2 domain. Five of the mutations were recurrent. Interestingly, no mutations in the PTPN11 gene were detected in five additional patients with cardio-facio-cutaneous (CFC) syndrome, which shows clinical similarities to NS.

We report three generation family that includes two patients with severe mental retardation and additional anomalies who have been studied, clinically, cytogenetically, and molecular cytogenetically. A clinical diagnosis could not be made in the propositus, but facial anomalies of Down syndrome (DS) were recognized in the maternal uncle of the propositus. In view of a strong family history of recurrent miscarriage, a familial translocation was highly suggestive. Standard cytogenetic analysis did not reveal any abnormalities. Fluorescence in situ hybridization (FISH) using subtelomeric DNA probes identified a familial cryptic translocation of chromosomes 18 and 21, resulting in partial trisomy 21 and partial monosomy 18q in both patients. FISH analysis of obligate carriers demonstrated a balanced translocation between the terminal parts of 18q and 21q. Including this family, a total of six different familial cases with cryptic or subtle subtelomeric translocations of chromosome 21q has been reported, of which three involved terminal parts of chromosome 18q. The remarkable similarity of the chromosomal breakpoints of our patients and the described families prompted us to refine the breakpoints and to discuss phenotypic differences between these patients. Our results reinforce the role of cryptic subtelomeric rearrangements in patients with mental retardation associated with physical anomalies and stress the importance of FISH technology to supplement routine cytogenetics.

Mutations in the gene for fibrillin-1 (FBN1) cause Marfan syndrome, an autosomal dominant disorder of connective tissue with prominent manifestations in the skeletal, ocular, and cardiovascular system. There is a remarkable degree of clinical variability both within and between families with Marfan syndrome as well as in individuals with related disorders of connective tissue caused by FBN1 mutations and collectively termed type-1 fibrillinopathies. The so-called neonatal region in FBN1 exons 24-32 comprises one of the few generally accepted genotype-phenotype correlations described to date. In this work, we report 12 FBN1 mutations identified by temperature-gradient gel electrophoresis screening of exons 24-40 in 127 individuals with Marfan syndrome or related disorders. The data reported here, together with other published reports, document a significant clustering of mutations in exons 24-32. Although all reported mutations associated with neonatal Marfan syndrome and the majority of point mutations associated with atypically severe presentations have been found in exons 24-32, mutations associated with classic Marfan syndrome occur in this region as well. It is not possible to predict whether a given mutation in exons 24-32 will be associated with classic, atypically severe, or neonatal Marfan syndrome.

Rubinstein-Taybi syndrome (RTS) is a dominant Mendelian disorder characterised by mental retardation, a typical facies, broad thumbs and short stature. Previous reports indicated that 4-25% of RTS patients have a submicroscopic 16p13.3 deletion of the CBP gene. Using FISH and cosmid probes RT100, RT191 and RT203 we studied 45 RTS patients from Germany, the Czech Republic, Austria and Turkey and found four deletions (8.9%, pooled data including other studies: 11%). All deletions were interstitial; three spanned the CBP gene (RT100-RT203) and one was smaller (RT100 only). Previous studies reported no phenotype-genotype correlation between RTS patients with or without a deletion. Our findings suggest a more severe phenotype. The mean age at presentation was 0.96 years in patients with a deletion as against 11.12 years in those without. Patients A and B with a deletion died in infancy which is rare in RTS and was not observed among the other patients. Patients A and D had accessory spleens, Patient A with hypoplastic left heart, abnormal pulmonary lobulation and renal agenesis. This is the second report of hypoplastic left heart and the first report of polysplenia with RTS. The signs suggest a developmental field defect (disturbance of laterality) either as a newly recognised pattern of RTS, or alternatively a novel contiguous gene syndrome.

Die Assoziation von kongenitalen Hypoparathyreoidismus, sensorineuraler Schwerhorigkeit und Nierendysplasie ist ein autosomal-dominantes Krankheitsbild mit variabler Expressivitat. Wir beschreiben eine Familie (Vater und Sohn), in welcher der Hypoparathyreoidismus beim Vater relativ spat erkannt wurde bzw. beim Sohn symptomlos blieb und die sensorineurale Horstorung jeweils schon seit fruher Kindheit bestand. Beim Vater besteht eine chronische Niereninsuffizienz im Stadium der Kompensation, der Sohn wurde bereits einseitig nephrektomiert. Zudem haben Vater und Sohn ein uberzahliges Markerchromosom, welches molekularzytogenetisch als ein isodizentrisches Chromosom 22q11 identifiziert wurde. Die gesunden Familienmitglieder haben das Markerchromosom nicht. Diskussion: Wir vermuten, das das Markerchromosom 22q11 eine Bedeutung fur den Phanotyp haben konnte.

Wir berichten uber ein 3jahriges Madchen, das wegen statomotorischer und mentaler Retardierung, generalisierter Muskelhypotonie und ubermasigem Wachstum zur klinisch-genetischen Diagnostik kam. Zytogenetisch wurde eine De-novo-Deletion 22q13 festgestellt. In der Literatur wurden 7 Patienten mit einem ahnlichen Phanotyp beschrieben. Diskussion: Es ist zu vermuten, das im Deletionsintervall 22q ein Wachstumsgen liegt.

We report on a 5-year-old boy with bilateral coloboma of iris, short stature, moderate developmental delay, and a few minor craniofacial anomalies. High-resolution GTG banding showed a small distal deletion of one chromosome 16 [del(16)(q23.1q24.2)]. Molecular refinement of the deletion breakpoints yielded that the proximal breakpoint at 16q23.1 is located between loci D16S395 (present) and D16S348 (absent). Comparison with previously published cases of deletion 16q demonstrated that the clinical phenotype is not a recognizable 16q- syndrome and different from the two cases of deletions of 16(q22.1 to q24.1) described by Callen et al. [1993]. Evidently, deletion 16(q23.1q24.2) has a milder phenotypic effect than other interstitial and distal 16q deletions.

ICF syndrome (ICFS) is a rare immunodeficiency disorder characterized by instability of the pericentromeric heterochromatin predominantly of chromosomes 1 and 16. DNA methylation studies in two unrelated ICFS patients provide further evidence for a marked hypomethylation of satellite 2 DNA. The ICFS-specific disturbances of chromatin structure take place within the satellite 2 DNA regions, as demonstrated by fluorescence in situ hybridization analysis. Moreover, methylation studies of genomic imprinted loci D15S63, D15S9, and H19 have revealed hypomethylation to different degrees in both patients; this provides evidence for hypomethylation at autosomal single copy loci in ICFS. Cell fusion experiments have revealed a distinct reduction of chromosomal abnormalities in ICFS cells after fusion with normal cells, suggesting that the abnormalities are caused by the loss of function of an as yet unknown trans acting factor. Although it is now clear that wide-spread DNA hypomethylation is a characteristic feature of ICFS, neither the cause and mechanism of hypomethylation nor their relationship to the clinical symptoms is known. We speculate that a phenotypic effect might result from tissue-dependent abnormal gene expression and/or from a possible structural disturbance of DNA domains, which, with respect to the immunodeficiency, partially prevents the normal somatic recombinations in immunologically active cells.

To date, 32 cases of partial 7p monosomy have been described, 14 of which have been associated with craniosynostosis (CRS). There is considerable variation in the size and location of the deleted segment. However, CRS appears to be consistently associated with either a deletion or partial deletion 7p21-->7p22 or more rarely a deletion of 7p13-->7p14. Analysis of a panel of six 7p deletion cases (three with CRS) was undertaken using informative DNA probes, in order to characterize and define the extent of the deletions at the molecular level. There were five de novo deletions and one resulting from the unbalanced product of a paternal balanced insertion. The putative proximal CRS locus at 7p13-->7p14 does not appear to be allelic with Greig cephalopolysyndactyly syndrome. Three probe positions have been refined: pJ5.11 (D7S10) previously mapped to 7p14-->pter does not appear to map proximal to p15; TM102L (D7S135) does not map distal to p22; CRI-P137 (D7S65) maps distal to 7p13.

The study of the fetal platelet count and size can, according to the literature, be used for the prenatal diagnosis of the Wiskott-Aldrich syndrome (WAS). So far, no affected fetuses have been identified by this method. All pregnancies in which this method had been applied to resulted, as correctly predicted, in the birth of normal children. Here we report on a familial case of WAS where the haematological parameters failed to reveal the affected second child. Hence we assume that the platelet count and size of platelets remain normal in fetuses with WAS to the gestational age of 22 weeks and cannot be used for prenatal diagnosis.

By means of an appropriate mathematical model (Sager's 2-components-concept) a delayed spontaneous pubertal growth spurt can be demonstrated in girls with 45,X Ullrich-Turner syndrome (UTS) (n1 = 45) as well as in those with 45,X/46,XX mosaicism (n2 = 14) never treated with any growth stimulating drug. On the average, this growth spurt begins later and its extent is smaller (mean growth rate = 3.10 and 2.79 cm, respectively, in the 15th year of chronological age) than in normal girls. The delay in acute growth spurt corresponds very well to the delay of skeletal maturation in the UTS (on the average 2 to 3 years of chronological age).

Submicroscopic or subtle aneusomies at the chromosome ends, typically diagnosed by subtelomere fluorescence in situ hybridization (FISH), are a significant cause of idiopathic mental retardation (MR). Some 20 subtelomere studies, including more than 2,500 subjects, have been reported. The studies are not directly comparable because different techniques and patient ascertainment criteria were used, but an analysis of 14 studies showed that aberrations were detected in 97 out of 1,718 patients (5.8%, range 2-29%; 95% confidence interval (CI) 4.60-6.84%). We performed a subtelomere FISH study of 50 unrelated children ascertained by a checklist that evaluates MR or developmental delay, dysmorphism, growth defect, and abnormal pedigree and found 10 bona fide causal rearrangements (detection rate 20%, 95% CI 10-33.7%). The findings included five unbalanced familial translocations or inversions, two unbalanced de novo translocations, and two de novo deletions. Patient 5 showed multiple anomalies (large head, vision defect, omphalocele, heart defect, enlarged kidneys, moderate MR, speech defect, mild transient homocysteinemia) and a de novo balanced translocation of chromosomes 17p13.3 and 20q13.33. The report of a subtelomeric balanced rearrangement associated with a disease phenotype is a novel one. FISH mapping using panels of overlapping BAC clones identified a number of candidate genes at or near his breakpoints, including ASPA, TRPV3, TRPV1, and CTNS at 17p13.3, and three genes of unknown function at 20q13.33. Only the homocysteinemia could be speculatively linked to one of these genes (CTNS, the gene for cystinosis). Three within the subset of 16 children (18.8%) with mild (IQ, 50-69) or unspecified degree of MR tested positive, suggesting that the checklist approach could be especially useful within this group of patients.

We report clinical, cytogenetic, and molecular cytogenetic studies on four patients with subtle or submicroscopic 7q36 deletions either of de novo origin or resulting from a cryptic parental translocation. Fluorescence in situ hybridization (FISH) studies indicated that in all four patients, the Sonic Hedgehog gene (SHH) and the homeobox gene HLXB9, among others, are comprised in the deletions. Besides mental retardation and short stature, all patients showed only minimal manifestations of the holoprosencephaly (HPE) spectrum and only one displayed symptoms of the Currarino syndrome. Patient 1 had a de novo 7q36.1-qter deletion and showed microcephaly, ptosis, sacral agenesis, tethered cord, but no structural brain anomaly. Patient 2 had a submicroscopic de novo 7q36 deletion detected by FISH, and showed facial and cerebral microsigns of the HPE spectrum. Patient 3 had a 7q36 deletion found by subtelomere FISH testing that was the unbalanced product of a subtle maternal 7q;10q translocation. She presented facial and ocular microsigns, but no structural abnormality of the brain. Patient 4 showed no specific syndromal pattern and was found to have a cryptic unbalanced de novo translocation of the terminal parts of chromosomes 7q and 9p by subtelomere FISH. Patients 2, 3, and 4 represent the first report of a de novo submicroscopic 7q36 deletion, the second report of a familial subtle translocation of 7q36, and the first report of an unbalanced de novo submicroscopic translocation of 7q36, respectively. Our results stress the importance of 7q36 deletion studies by FISH in patients with microsigns of the HPE spectrum.

Since 1990 avoidance of methylene blue as a dye in diagnostic amniocentesis is recommended. This is the result of the observation that a high incidence of jejuno-ileal atresia appeared in twin pregnancies following intraamniotic injection of methylene blue. We report a case of jejunal atresia in twins after injection of toluidine blue. We describe the clinical course, discuss possible teratogenic mechanisms and emphasize that no synthetic dyes should be used in second trimester amniocentesis.

We report three generation family that includes two patients with severe mental retardation and additional anomalies who have been studied, clinically, cytogenetically, and molecular cytogenetically. A clinical diagnosis could not be made in the propositus, but facial anomalies of Down syndrome (DS) were recognized in the maternal uncle of the propositus. In view of a strong family history of recurrent miscarriage, a familial translocation was highly suggestive. Standard cytogenetic analysis did not reveal any abnormalities. Fluorescence in situ hybridization (FISH) using subtelomeric DNA probes identified a familial cryptic translocation of chromosomes 18 and 21, resulting in partial trisomy 21 and partial monosomy 18q in both patients. FISH analysis of obligate carriers demonstrated a balanced translocation between the terminal parts of 18q and 21q. Including this family, a total of six different familial cases with cryptic or subtle subtelomeric translocations of chromosome 21q has been reported, of which three involved terminal parts of chromosome 18q. The remarkable similarity of the chromosomal breakpoints of our patients and the described families prompted us to refine the breakpoints and to discuss phenotypic differences between these patients. Our results reinforce the role of cryptic subtelomeric rearrangements in patients with mental retardation associated with physical anomalies and stress the importance of FISH technology to supplement routine cytogenetics.

Tricho-rhino-phalangeal syndrome (TRPS) is characterized by craniofacial and skeletal abnormalities. Three subtypes have been described: TRPS I, caused by mutations in the TRPS1 gene on chromosome 8; TRPS II, a microdeletion syndrome affecting the TRPS1 and EXT1 genes; and TRPS III, a form with severe brachydactyly, due to short metacarpals, and severe short stature, but without exostoses. To investigate whether TRPS III is caused by TRPS1 mutations and to establish a genotype-phenotype correlation in TRPS, we performed extensive mutation analysis and evaluated the height and degree of brachydactyly in patients with TRPS I or TRPS III. We found 35 different mutations in 44 of 51 unrelated patients. The detection rate (86%) indicates that TRPS1 is the major locus for TRPS I and TRPS III. We did not find any mutation in the parents of sporadic patients or in apparently healthy relatives of familial patients, indicating complete penetrance of TRPS1 mutations. Evaluation of skeletal abnormalities of patients with TRPS1 mutations revealed a wide clinical spectrum. The phenotype was variable in unrelated, age- and sex-matched patients with identical mutations, as well as in families. Four of the five missense mutations alter the GATA DNA-binding zinc finger, and six of the seven unrelated patients with these mutations may be classified as having TRPS III. Our data indicate that TRPS III is at the severe end of the TRPS spectrum and that it is most often caused by a specific class of mutations in the TRPS1 gene.

Patients with deletions in 22q13 are known to have phenotypic features that include normal or accelerated growth, large hands and feet, hypotonia, delayed psychomotor development and mild facial dysmorphism. To date, very few cases have been investigated by detailed molecular genetic analysis. We have analyzed three new patients with terminal deletions in 22q. We compared the cytogenetic observations with molecular data assessed by fluorescence in situ hybridization and an array of characterized bacterial artificial chromosome recombinants. The shortest region of deletion overlap is localized in 22q13.2–qter distal to the marker D22S94, but the telomeric repeat in the deleted chromosome appears to remain intact. When parental alleles were investigated in two of the three patients, the aberrant homolog was found to be of paternal origin in both cases. Although the deleted region still spans >20 cM, molecular analysis of additional patients and screening for new genes might help in elucidating candidate genes connected with the dysmorphisms defined by deletions of 22q13.

We describe a 17-month-old infant with clinical features of Down syndrome and a normal karyotype by standard chromosomal analysis, her two uncles aged 28 and 30 years, respectively, with reduced intelligence and unusual appearance but not apparent Down syndrome, and a severely retarded 6-year-old girl with dysmorphy and epilepsy from the same family. Cytogenetic studies of patients and normal intervening relatives had been carried out at different institutions with normal results. Fluorescence in situ hybridization using whole chromosome painting and unique-copy probes (cosmids) and high-resolution banding revealed a familial subtelomeric translocation of chromosomes 18 and 21, resulting in partial trisomy 21 in the infant and her two uncles, and partial monosomy 21 in the 6-year-old girl. Cytogenetic breakpoints were located in bands 18q23 and 21q22.1, respectively. The molecular breakpoint on chromosome 21 was located between D21S211 (proximal) and D21S1283 (distal) and thus maps within the Down syndrome critical region.

Two unrelated patients with small distal deletions of the long arm of chromosome 13 are described, with shawl scrotum and penoscrotal transposition, penoscrotal hypospadias, a reduced perineum, and anal atresia. The patients have small deletions of 13(q32.2qter) and 13(q32q34), respectively. This report and the literature present evidence for one or possibly more gene(s) within region 13q32.2q34 which regulate the development of the ano-genital structures. The clinical spectrum includes bifid or shawl scrotum, hypospadias, biseptate uterus, malplaced and imperforate anus, and common cloaca.

Pseudohypoaldosteronism is thought to be a rare salt-losing disorder, caused by resistance to the action of aldosterone. Defective aldosterone receptor binding is present in familial as well as sporadic cases and it has been suggested that the pathogenesis is due to a defect in the aldosterone receptor system. To date, however, molecular genetic analysis has been unable to identify a mutation in the aldosterone receptor gene itself. We have reviewed the findings in patients with pseudohypoaldosteronism, for clues which might enable us to identify the underlying pathogenesis. Although aldosterone receptor binding is regularly decreased or absent in monocytes of patients with pseudohypoaldosteronism, in some patients receptor protein can be detected with a fluorescencelabeled antibody. Receptor protein was detected in patients from familial autosomal dominant families and in sporadic cases, but was undetectable in two patients with the familial recessive form. To further elucidate the pattern of inheritance we studied the response of the renin-angiotensin-aldosterone system to the stimulation by sodium depletion in the familial autosomal dominant form and in two families with sporadic cases. In both “sporadic” families investigated, one parent and one sibling had an exaggerated response of renin and aldosterone to sodium depletion indicating a defect of sodium conservation apparent only during stress, leading to reclassification as familial cases. No additional family member in the “classical” autosomal dominant families responded abnormally to sodium depletion. These findings indicate that pseudohypoaldosteronism is unusually heterogeneous in its clinical, biochemical, and genetic presentations and findings and suggest that its pathogenesis is heterogeneous as well.

Cytogenetic analysis of a 20-year-old sterile male revealed a 45,X0 karyotype with no evidence for Y-chromosomal material on any of the chromosomes analysed by Q-, G- and C-banding. DNA analysis with 17 different Y chromosome-derived probes revealed the presence of Yp DNA sequences in the patient's genome. In situ hybridization with the Yp-derived probe pJA36B disclosed a translocation of Y-chromosomal material onto the short arm of a chromosome 22.

We report on a boy with a characteristic combination of facial anomalies, syndactylies of fingers and toes, and mental retardation. Scott et al. (Journal of Pediatrics 78:658-663, 1971) observed 3 brothers with almost identical manifestations. The mother of these patients had bilateral syndactyly of toes 2 and 3. This led the authors to suggest X-linked inheritance. The mother of our patient also has cutaneous syndactyly between the second and third toes, strengthening the hypothesis of X-linked inheritance.

Disease-specific growth curves for Turner's syndrome were calculated by means of 2nd order homogeneous differential equations with constant coefficients, taking different cytogenetical subtypes into account. Comparison of these growth curves between X-monosomic (n = 64) and 46,XX/45,X-mixoploid (n = 20) patients reveals no differences, in contrast to the commonly accepted opinion.