Langer-Giedion syndrome and additional congenital malformations with interstitial deletion of the long arm of chromosome 8 46, XY, del 8 (q 13-22)

Long-term follow-up of four patients with Langer-Giedion syndrome: clinical course and complications

Long-term observations of individuals with the so-called Langer-Giedion (LGS) or tricho-rhino-phalangeal type II (TRPS2) are scarce. We report here a on follow-up of four LGS individuals, including one first described by Andres Giedion in 1969, and review the sparse publications on adults with this syndrome which comprises ectodermal dysplasia, multiple cone-shaped epiphyses prior to puberty, multiple cartilaginous exostoses, and mostly mild intellectual impairment. LGS is caused by deletion of the chromosomal segment 8q24.11-q24.13 containing among others the genes EXT1 and TRPS1. Most patients with TRPS2 are only borderline or mildly cognitively delayed, and few are of normal intelligence. Their practical skills are better than their intellectual capability, and, for this reason and because of their low self-esteem, they are often underestimated. Some patients develop seizures at variable age. Osteomas on processes of cervical vertebrae may cause pressure on cervical nerves or dissection of cerebral arteries. Joint stiffness is observed during childhood and changes later to joint laxity causing instability and proneness to trauma. Perthes disease is not rare. Almost all males become bald at or soon after puberty, and some develop (pseudo) gynecomastia. Growth hormone deficiency was found in a few patients, TSH deficiency so far only in one. Puberty and fertility are diminished, and no instance of transmission of the deletion from a non-mosaic parent to a child has been observed so far. Several affected females had vaginal atresia with consequent hydrometrocolpos.

Disorders caused by chromosome abnormalities

Many human genetic disorders result from unbalanced chromosome abnormalities, in which there is a net gain or loss of genetic material. Such imbalances often disrupt large numbers of dosage-sensitive, developmentally important genes and result in specific and complex phenotypes. Alternately, some chromosomal syndromes may be caused by a deletion or duplication of a single gene with pleiotropic effects. Traditionally, chromosome abnormalities were identified by visual inspection of the chromosomes under a microscope. The use of molecular cytogenetic technologies, such as fluorescence in situ hybridization and microarrays, has allowed for the identification of cryptic or submicroscopic imbalances, which are not visible under the light microscope. Microarrays have allowed for the identification of numerous new syndromes through a genotype-first approach in which patients with the same or overlapping genomic alterations are identified and then the phenotypes are described. Because many chromosomal alterations are large and encompass numerous genes, the ascertainment of individuals with overlapping deletions and varying clinical features may allow researchers to narrow the region in which to search for candidate genes.

Clinical and molecular characterization of a patient with Langer-Giedion syndrome and mosaic del(8)(q22.3q24.13)

The tricho-rhino-phalangeal syndrome type II (TRPS II) is characterized by sparse scalp hair, a long nose with a bulbous tip, a long flat philtrum, cone-shaped epiphyses of the phalanges, retarded bone age in infancy and multiple cartilaginous exostoses. All patients have a hemizygous deletion on chromosome 8q23.3-24.11 which spans at least the 2.8 Mb-region from TRPS1 through EXT1. Only patients with deletions that extend beyond this interval tend to have mental retardation. Here we describe a 14.5-year-old girl with mental retardation and TRPS II. Her facial features are only mild, but she has the typical skeletal features including cone-shaped epiphyses at the phalanges, retarded bone age, multiple exostoses and short stature. She is the first patient with TRPS II and a molecularly proven mosaic interstitial deletion in 8q22.3-q24.13. The deletion is one of the largest ever found in TRPS II, and spans 19.79 Mb and 50 genes or loci including TRPS1 and EXT1. The degree of mosaicism is 7% in lymphocytes from peripheral blood and 97% in skin fibroblasts.

The discovery of microdeletion syndromes in the post-genomic era: review of the methodology and characterization of a new 1q41q42 microdeletion syndrome

PURPOSE

The advent of molecular cytogenetic technologies has altered the means by which new microdeletion syndromes are identified. Whereas the cytogenetic basis of microdeletion syndromes has traditionally depended on the serendipitous ascertainment of a patient with established clinical features and a chromosomal rearrangement visible by G-banding, comparative genomic hybridization using microarrays has enabled the identification of novel, recurrent imbalances in patients with mental retardation and apparently nonspecific features. Compared with the "phenotype-first" approach of traditional cytogenetics, array-based comparative genomic hybridization has enabled the detection of novel genomic disorders using a "genotype-first" approach. We report as an illustrative example the characterization of a novel microdeletion syndrome of 1q41q42.

METHODS

We tested more than 10,000 patients with developmental disabilities by array-based comparative genomic hybridization using our targeted microarray. High-resolution microarray analysis was performed using oligonucleotide microarrays for patients in whom deletions of 1q41q42 were identified. Fluorescence in situ hybridization was performed to confirm all 1q deletions in the patients and to exclude deletions or other chromosomal rearrangements in the parents.

RESULTS

Seven cases were found with de novo deletions of 1q41q42. The smallest region of overlap is 1.17 Mb and encompasses five genes, including DISP1, a gene involved in the sonic hedgehog signaling pathway, the deletion of which has been implicated in holoprosencephaly in mice. Although none of these patients showed frank holoprosencephaly, many had other midline defects (cleft palate, diaphragmatic hernia), seizures, and mental retardation or developmental delay. Dysmorphic features are present in all patients at varying degrees. Some patients showed more severe phenotypes and carry the clinical diagnosis of Fryns syndrome.

CONCLUSIONS

This new microdeletion syndrome with its variable clinical presentation may be responsible for a proportion of Fryns syndrome patients and adds to the increasing number of new syndromes identified with array-based comparative genomic hybridization. The genotype-first approach to identifying recurrent chromosome abnormalities is contrasted with the traditional phenotype-first approach. Targeting developmental pathways in a functional approach to diagnostics may lead to the identification of additional microdeletion syndromes.

Trichorhinophalangeal syndrome type II without the chromosome 8 deletion that resembled metachondromatosis

We describe a 5-year-old girl with features resembling Trichorhinophalangeal syndrome, type I (sparse scalp hair, bushy eyebrows, bulbous nose, long philtrum, cone-shaped epiphyses, clinobrachydactyly, epiphyseal changes in the femoral head and short stature), and appendicular exostoses similar to trichorhinophalangeal syndrome, type II. However, despite physical resemblance to the trichorhinophalangeal syndrome variants, cytological analysis showed a structurally normal chromosome 8 and no mental deficiency was apparent. In addition, morphological congruities between multiple exostoses and metachondromatosis was indicated from radiographic findings.

Nablus mask-like facial syndrome is caused by a microdeletion of 8q detected by array-based comparative genomic hybridization

In 2000, Teebi reported on a 4-year-old boy with a distinctive pattern of malformation, which he termed the "Nablus mask-like facial syndrome" (OMIM# 608156). Characterization of this syndrome has been difficult because of the paucity of patients described in the medical literature and its unknown etiology and pathogenesis. We present two patients with Nablus mask-like facial syndrome who both display a microdeletion in the 8q21-8q22 region detected by array-based comparative genomic hybridization. Patient 1, a boy, has a distinct facial appearance characterized by severe blepharophimosis, tight-appearing glistening facial skin, sparse and unruly hair, a flat and broad nose, and distinctive ears that are triangular in shape with prominent antihelices. He also demonstrates camptodactyly, contractures, unusual dentition, cryptorchidism, mild developmental delay, and a happy demeanor. Patient 2, a girl with a strikingly similar phenotype, was previously described in a report by Salpietro et al. 2003. She has distinctive ears, dental anomalies, and developmental delay. The etiology of her pattern of malformation was not identified at that time. Although high-resolution chromosome and subtelomeric FISH analyses were normal, array-based comparative genomic hybridization revealed an approximately 4 Mb deletion involving the 8q21.3-8q22.1 region in both patients. This region encompasses a number of genes that may contribute to this unique phenotype. These results demonstrate a chromosomal microdeletion as the etiology of Nablus mask-like facial syndrome and emphasize the diagnostic utility of array-based comparative genomic hybridization in the evaluation of multiple malformation syndromes of previously unrecognized causation.

Pronounced short stature in a girl with tricho-rhino-phalangeal syndrome II (TRPS II, Langer-Giedion syndrome) and growth hormone deficiency

We report on a 10-year-old girl with tricho-rhino-phalangeal syndrome type II (TRPS II) and pronounced short stature (-4.8 SD). The patient has an interstitial chromosome 8q24.1 deletion of 12-15 Mb. The deletion spans all genes from CSMD3 to at least ANXA13 including the TRPS1 and EXT1 genes, which are responsible for the TRPS II phenotype. In addition to the features of TRPS II, the patient had growth hormone (GH) deficiency with diminished response in three stimulation tests. Therapy with 0.2 mg GH/kg/week led to an increase of growth velocity from 2.5 to 6.6 cm/year. To our knowledge, such a combination of TRPS II and GH deficiency has not yet been described.

Chromosomal abnormalities and epilepsy: a review for clinicians and gene hunters

PURPOSE

We analyzed databases on chromosomal anomalies and epilepsy to identify chromosomal regions where abnormalities are associated with clinically recognizable epilepsy syndromes. The expectation was that these regions could then be offered as targets in the search for epilepsy genes.

METHODS

The cytogenetic program of the Oxford Medical Database, and the PubMed database were used to identify chromosomal aberrations associated with seizures and/or EEG abnormalities. The literature on selected small anomalies thus identified was reviewed from a clinical and electroencephalographic viewpoint, to classify the seizures and syndromes according to the current International League Against Epilepsy (ILAE) classification.

RESULTS

There were 400 different chromosomal imbalances described with seizures or EEG abnormalities. Eight chromosomal disorders had a high association with epilepsy. These comprised: the Wolf-Hirschhorn (4p-) syndrome, Miller-Dieker syndrome (del 17p13.3), Angelman syndrome (del 15q11-q13), the inversion duplication 15 syndrome, terminal deletions of chromosome 1q and 1p, and ring chromosomes 14 and 20. Many other segments had a weaker association with seizures. The poor quality of description of the epileptology in many reports thwarted an attempt to make precise karyotype-phenotype correlations.

CONCLUSIONS

We identified certain chromosomal regions where aberrations had an evident association with seizures, and these regions may be useful targets for gene hunters. New correlations with specific epilepsy syndromes were not revealed. Clinicians should continue to search for small chromosomal abnormalities associated with specific epilepsy syndromes that could provide important clues for finding epilepsy genes, and the epileptology should be rigorously characterized.

The link between cytogenetics and mendelism

High resolution chromosome analysis, molecular cytogenetics, and study of the association between specific chromosome rearrangements and single gene disorders have provided a chromosomal basis to a number of mendelian diseases. Deletions and duplications of small regions, usually less than 3 Mb in size, result in an alteration of normal gene dosage of a number of unrelated genes physically close to each other and are responsible for contiguous gene syndromes. For example, haploinsufficiency is implicated for del 8q24.1 in Langer-Giedion syndrome, del 17p13.3 in Miller-Dieker syndrome, and del 22q11.2 in DiGeorge and Velo-cardiofacial syndromes. Another chromosomal mechanism causing mendelian phenotypes is translocation, which may eventually interrupt a disease gene. It is assumed that translocation breakpoints are running through a relevant gene, hindering the production of the gene product. An example is breakage 16p13.3 associated with Rubinstein-Taybi syndrome. Females with X/autosome translocations have an almost exclusive inactivation of the normal X. Interruption of a disease gene in the translocated X causes the expression of a mendelian phenotype in the presence of an allelic recessive mutation onto the nonrearranged X. Finally, if a human gene shows exclusive expression from a single parental homologue, ie, it is imprinted, deletion of the chromosomal segment containing the active allele results in structural monosomy and functional nullisomy. This situation is illustrated by Prader-Willi and Angelman syndromes. Over seventy human genes have been precisely assigned to chromosomal regions using a cytogenetic approach. Chromosome techniques combined with molecular methods have proved to have powerful and sensitive diagnostic capabilities.

An association between psoriasis and hereditary multiple exostoses. A clue for the mapping of a psoriasis susceptibility gene?

Chronic plaque psoriasis affects approximately 1.6% of the U.K. population. Population, family and twin studies all strongly suggest an important genetic component in the pathogenesis of the disease, although genetic linkage studies have, so far, failed to identify susceptibility genes. We describe a family in which psoriasis cosegregates through three generations with a known autosomal dominant disorder, hereditary multiple exostoses (HME). A major locus for HME has recently been mapped to chromosome 8q. Observations in this family may provide a mapping clue for a psoriasis susceptibility gene.

Interstitial deletion of 8q13.3-->22.1 associated with craniosynostosis

We report on a 3-year-old girl who has an interstitial deletion of chromosome 8q [46,XX,del(8)(q13.3q22.1)]. She has severe mental retardation and minor anomalies in addition to lambdoidal synostosis. This is the first report of craniosynostosis in association with this chromosomal deletion. The manifestations of our patient are compared to those of previously reported patients with similar deletions.

Tricho-rhino-phalangeal syndrome type I (TRP I) due to an apparently balanced translocation involving 8q24

Tricho-rhino-phalangeal (TRP) syndromes type I and II are caused by a defective gene located on chromosome 8q24.1. We report a family with 2 sibs affected with TRP type I in combination with an apparently balanced chromosome (8;18) translocation involving 8q24.11. It is very likely that the 8q24 translocation breakpoint is physically linked to the TRP gene(s), thereby facilitating future efforts to clone the TRP gene(s).

Tricho-rhino-phalangeal syndrome type II (Langer-Giedion) with persistent cloaca and prune belly sequence in a girl with 8q interstitial deletion

A patient with the diagnosis of Langer-Giedion syndrome (tricho-rhino-phalangeal syndrome type II) and interstitial 8q deletion was also noted to have persistent cloaca and prune belly sequence. This is the first report of this association. If it postulated that these latter embryonic defects may be due to the chromosome abnormality, supporting the definition of contiguous gene syndrome.

The gene for hereditary multiple exostoses does not map to the Langer-Giedion region (8q23-q24)

Hereditary multiple exostoses is a dominantly inherited skeletal disorder which alters enchondral bone during growth and is characterised by exostoses of the juxta-epiphyseal regions. Using polymorphic DNA probes, we have been able to exclude the disease gene from close proximity to the 8q24.1 region where a dominant syndrome with multiple exostoses, the trichorhinophalangeal syndrome type II (TRP II, Langer-Giedion syndrome, MIM 15025), has been previously localised (pairwise linkage Z = -8.96 at theta = 0 with probe L48 at locus D8S51). Multipoint linkage analysis using probes L48, L24, and L1 consistently excluded the HME gene from a large area of the distal long arm of chromosome 8, spanning the smallest region of overlap assigned to the TRP II gene. These studies support the clinical view that HME and TRP II are distinct entities.

Severe mental retardation in a patient with tricho-rhino-phalangeal syndrome type I and 8q deletion

We report a 19-year-old boy with an interstitial deletion of the long arm of chromosome 8 (46, XY, del(8)(pter----q23.3: :q24.13----qter)). He shows the typical clinical symptoms of tricho-rhino-phalangeal syndrome (TRPI) and severe mental retardation, however without multiple exostoses. This is the second report of a combination of abnormalities and interstitial deletion of 8q.

Maternal origin of a de novo chromosome 8 deletion in a patient with Langer-Giedion syndrome

The anonymous DNA probe L32, which defines the D8S48 locus within the Langer-Giedion syndrome chromosome region on the long arm of chromosome 8, was used to search for a common restriction fragment length polymorphism. A HindIII and an MspI polymorphism were detected (polymorphism information contents 0.25 and 0.19, respectively). Both polymorphisms were informative in the family of a Langer-Giedion patient carrying a de novo interstitial deletion 8q23-24.1. Lack of transmission of a maternal haplotype indicates that this deletion occurred during maternal gametogenesis. This finding contrasts with the frequent paternal origin of mutations in other microdeletion syndromes.

Cloning defined regions of the human genome by microdissection of banded chromosomes and enzymatic amplification

The molecular analysis of many genetic diseases requires the isolation of probes for defined human chromosome regions. Existing techniques such as the screening of chromosome-specific libraries, subtractive DNA cloning and chromosome jumping are either tedious or not generally applicable. Microdissection and microcloning has successfully been applied to various chromosome regions in Drosophila and mouse, but conventional microtechniques are too coarse and inefficient for analysis of the human genome. Because microdissection has previously been used on unbanded chromosomes only, cell lines in which the chromosome of interest could be identified without banding had to be used. At least one hundred chromosomes were needed for dissection and lambda vectors used to achieve maximum cloning efficiency. Recombinant phage clones are, however, more difficult to characterize than plasmid clones. Here we describe the dissection of the Langer-Giedion syndrome region on chromosome 8 from GTG-banded metaphase chromosomes (G-banding with trypsin-Giemsa) and the universal enzymatic amplification of the dissected DNA. Eighty per cent of clones from this library (total yield 20,000) identify single-copy DNA sequences. Fifty per cent of clones detect deletions in two patients with Langer-Giedion syndrome. Although the other clones have not yet been mapped, this result demonstrates that thousands of region-specific probes can be isolated within ten days.

Tricho-rhino-phalangeal syndrome type I with severe mental retardation due to interstitial deletion of 8q23.3-24.13

Here we report on a 13-year-old boy who had an interstitial deletion of the long arm of chromosome 8 [46,XY,del(8)(pter----q23.3::q24.13----qter)]. He had the facial features of the tricho-rhino-phalangeal (TRP) syndrome and severe mental retardation, but lacked multiple exostoses. This is the first report with such a peculiar combination of abnormalities and interstitial deletion of 8q.

Human chromosome 8

The role of human chromosome 8 in genetic disease together with the current status of the genetic linkage map for this chromosome is reviewed. Both hereditary genetic disease attributed to mutant alleles at gene loci on chromosome 8 and neoplastic disease owing to somatic mutation, particularly chromosomal translocations, are discussed.

Microdeletion syndromes, balanced translocations, and gene mapping

High resolution prometaphase chromosome banding has allowed the detection of discrete chromosome aberrations which escaped earlier metaphase examinations. Consistent tiny deletions have been detected in some well established malformation syndromes: an interstitial deletion in 15q11/12 in the majority of patients with the Prader-Willi syndrome and in a minority of patients with the Angelman (happy puppet) syndrome; a terminal deletion of 17p13.3 in most patients examined with the Miller-Dieker syndrome; an interstitial deletion of 8q23.3/24.1 in a large majority of patients with the Giedion-Langer syndrome; an interstitial deletion of 11p13 in virtually all patients with the WAGR (Wilms' tumour-aniridia-gonadoblastoma-retardation) syndrome; and an interstitial deletion in 22q11 in about one third of patients with the DiGeorge sequence. In addition, a combination of chromosome prometaphase banding and DNA marker studies has allowed the localisation of the genes for retinoblastoma and for Wilms' tumour and the clarification of both the autosomal recessive nature of the mutation and the possible somatic mutations by which the normal allele can be lost in retina and kidney cells. After a number of X linked genes had been mapped, discrete deletions in the X chromosome were detected by prometaphase banding with specific attention paid to the sites of the gene(s) in males who had from one to up to four different X linked disorders plus mental retardation. Furthermore, the detection of balanced translocations in probands with disorders caused by autosomal dominant or X linked genes has allowed a better insight into the localisation of these genes. In some females with X linked disorders, balanced X; autosomal translocations have allowed the localisation of X linked genes at the breakpoint on the X chromosome. Balanced autosome; autosome translocations segregating with autosomal dominant conditions have provided some clues to the gene location of these conditions. In two conditions, Greig cephalopolysyndactyly and dominant aniridia, two translocation families with one common breakpoint have allowed quite a confident location of the genes at the common breakpoint at 7p13 and 11p13, respectively.

Langer-Giedion syndrome with del 8 (q24.13-q24.22)

An 8-year-old boy with the features of Langer-Giedion syndrome except for short stature is described. Chromosome analysis using high resolution G-banding techniques revealed an interstitial deletion of the long arm of chromosome 8:46,XY,del(8)(q24.13-q24.22).

8q24.12 Interstitial deletion in trichorhinophalangeal syndrome type I

In the present report we present the first example of a small interstitial 8q24.12 deletion in a patient with trichorhinophalangeal syndrome type I.

Interstitial deletion of the long arm of chromosome 8 without Langer-Giedion syndrome

A case of interstitial deletion of the long arm of chromosome 8 is reported. A chromosome analysis by a high resolution banding revealed the abnormal karyotype, 46, XY, del (8) (q11.2q13). Although some reports describe an association of 8q deletion with the Langer-Giedion syndrome, this patient did not have the typical features of this syndrome. It was noted that the patient had amino aciduria, EEG and ECG abnormalities together with other pathological findings.

Tricho-rhino-phalangeal syndrome without exostoses, wih an interstitial deletion of 8q23

We report on a patient with the Tricho-Rhino-Phalangeal syndrome (TRPS) with normal mentation, without exostoses and with a partial microdeletion of 8q23. Although she had the phenotypic characteristics of TRPS Type I, karyotypic analysis demonstrated the 8q-microdeletion usually associated with TRPS Type II, in which exostoses are present. Our patient represents the second reported instance of this phenotypic chromosomal association and provides further evidence for homogeneity of the TRPS.

A complex rearrangement, including a deleted 8q, in a case of Langer-Giedion syndrome

A 10-month-old infant with failure to thrive, delayed development, mild dysmorphia, cardiac anomalies, and cryptorchidism was referred for cytogenetic evaluation. Routine GTG-banded analysis revealed a modal number of 46 chromosomes, which contained an obvious complex rearrangement involving chromosomes 1, 8, and 14. Parental chromosomes were normal. Following high resolution techniques, this de novo rearrangement demonstrated an intraband deletion and was designated as [46,XY,t(1;8;14)(1pter----1p13.1::14q12----14pter++ +;1qter----1p13.1::8q24.13----8qter; 14qter----14q12::8p23.3----8q24.11:)]. Although deletions have been implicated as possibly responsible for abnormal phenotypes in patients with de novo "balanced rearrangements", in most cases, they could not be demonstrated. The present case is only the second instance documenting a subtle intraband deletion in association with a complex translocation. Fourteen of the reported 18 patients with an 8q deletion (including this infant) have Langer-Giedion syndrome, suggesting an etiologic relationship. However, the same deletion is not present in all cases.

The tricho-rhino-phalangeal syndrome(s): chromosome 8 long arm deletion: is there a shortest region of overlap between reported cases? TRP I and TRP II syndromes: are they separate entities?

Critical cytogenetic (re)evaluation of 2 of our own cases of tricho-rhino-phalangeal syndrome II (TRP II), or Langer-Giedion syndrome (LGS), and 10 cases from the literature, suggests that the shortest region of overlap of the 8q deletion is a part of band q24.1. This region is assumed to be causally related to this syndrome, and possibly also to TRP I syndrome which, therefore, may not be a causally separate entity.

The tricho-rhino-phalangeal syndrome with exostoses (or Langer-Giedion syndrome): four additional patients without mental retardation and review of the literature

We report on four patients with tricho-rhino-phalangeal syndrome with exostoses (TRPSE) who were not mentally retarded and review 32 previously published cases. These data enable more complete delineation of the phenotype and document the variability of the clinical and radiographic manifestations. Information on the genetics and the association with del(8q) is discussed, as are management and avenues for further investigation. The apparent variability of intelligence in TRPSE patients together with the high incidence of other problems, including significant delay in speech development and hearing loss, make systematic multidisciplinary evaluation and long-term treatment necessary to achieve the best outcome.

New chromosomal syndrome: Miller-Dieker syndrome and monosomy 17p13

The Miller-Dieker Syndrome (MDS) consists of lissencephaly, characteristic facies, pre- and postnatal growth retardation, plus various other birth defects. Autosomal recessive inheritance has been presumed based on four reported families with two or more affected siblings. We present substantial evidence that monosomy 17p13.3 causes the MDS phenotype. This includes two patients with ring chromosome 17, one patient with a de novo 17p13 deletion, and one patient with monosomy 17p due to an unbalanced 7p; 17p translocation. We report the first prenatal diagnosis of MDS in a 20-week fetus from this latter family. Additionally, we report a balanced translocation between chromosome 17 and different autosomes (8, 12, and 15) in three of the four familial cases of lissencephaly. The finding of a chromosomal basis for this presumed autosomal recessive disorder significantly alters genetic counseling and makes prenatal diagnosis possible in some families.

Terminal or interstitial deletion in chromosome 8 long arm in Langer-Giedion syndrome (TRP II syndrome)?

Reexamination with high resolution banding of the first ever published case of Langer-Giedion syndrome with 8q deletion as well as chromosome examination of a second case of this syndrome with different high resolution methods, confirmed our previous assumption of a terminal 8q involvement in the causation of TRP II syndrome.

Langer-Giedion syndrome and deletion of the long arm of chromosome 8. Confirmation of the critical segment to 8q23

In the present paper an intercalary deletion of band 8q23 is reported in another patient with Langer-Giedion syndrome. These data confirm that the deletion in 8q responsible for this malformation syndrome is located at band 8q23.

Two cases of the Langer-Giedion syndrome with the same interstitial deletion of the long arm of chromosome 8: 46, XY or XX, del (8) (q23.3q24.13)

Two cases of the Langer-Giedion syndrome (LGS) are reported. Chromosome analysis by high-resolution banding with 850 bands revealed the same abnormal karyotype, 46,XY or XX,del(8)(q23.3q24.13), which was the smallest deletion among those of LGS patients with 8q deletion. The deleted segments found in three patients with LGS analyzed by high-resolution banding have a part of 8q23.3 and 8q24.11 in common.

Langer-Giedion syndrome, in a child with complex structural aberration of chromosome 8

A patient with typical features of the Langer-Giedion syndrome (tricho-rhino-phalangeal syndrome, type II) is described. In the karyotype an interstitial deletion of the long arm of chromosome 8 (band 8q22) was observed as the result of a complex rearrangement of chromosomes 1 and 8: 46,XY inv(8)(q23 leads to q242), del(8)(q221 leads to q223), ins(8;1) (q221;p321 p341;q242). Previously reported cases of Langer-Giedion syndrome with deletion of 8q are compared with the present one.

Langer-Giedion syndrome with interstitial 8q-deletion

We describe a 12-year-old girl with Langer-Giedion syndrome (tricho-rhino-phalangeal syndrome type II) who also had vertebral malformations. Chromosome analysis identified an interstitial del(8q): 46,XX,del(8)(pter leads to q22::q234 leads to qter) as a cause of this syndrome.