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We report on an 18-month-old boy conceived by assisted reproduction technology with developmental delay, hypotonia, microcephaly, frontal bossing, a mild convergent squint, malformed ears, and a short neck. Karyotype analysis revealed a de novo 7q21.1q22.3 duplication characterized by array comparative genomic hybridization (array-CGH) as a segment of 18.69 Mb. Duplications of the long arm of chromosome 7 are uncommon. There are 18 reported cases of different 7q segments with a pure duplication with no additional deletion of other chromosomes. As a consequence, duplications of chromosome 7q have been classified in 4 groups on the basis of the involved region. The present case is included in group 3 which involves interstitial duplications of different sizes. In the literature, only one case with an apparently smaller duplication of the same region has been described. Despite this, the phenotype is different. Moreover, the 2 patients share some phenotypic features, such as psychomotor delay, hypotonia, frontal bossing, short neck, and strabismus. However, the absence of physical characterization in most of the reported cases could justify the lacking phenotype-genotype correlation in patients with partial 7q duplication. Further studies using recent molecular approaches such as array-CGH might permit a more clinically useful grouping of 7q duplications.

A chromosome mosaicism with two cell lines was diagnosed in a sterile man. One cell line had a 45, -Y, dup (X) (p22.2) karyotype and accounted for 83% of lymphocytes analyzed. Fluorescence in situ hybridization (FISH) analysis with specific X and Y probes excluded a translocation between the short arms of the X and Y chromosomes and showed that Xp duplication involved a region containing the DXS85 locus, distal to the ZFX and DSS sites. The other cell line consisted of a diploid karyotype with a rearranged Y chromosome, which was shown to be a pseudoisodicentric Yq by FISH. Moreover, FISH with a specific probe for the AZF locus and polymerase chain reaction using Yq SY108 and SY121 primers showed no signals for this region, possibly accounting for the azoospermia in this patient.

Twelve patients with different features of Turner syndrome, and with Xp and Yp rearrangements involving the pseudoautosomal region (PAR1) are described. In all patients, FISH analysis showed loss of one copy of the Short Stature Homeobox (SHOX)-containing gene. Ten patients had short stature and one disproportionate (mesomelic) normal stature, while the last one had normal stature. Skeletal abnormalities, including shortened ulna, were detected in nine subjects, and in six of them Madelung deformity was observed. These clinical data indicated a genotype phenotype correlation between haploinsufficiency of SHOX, and short stature and skeletal abnormalities.

Duane syndrome (MIM126800) is an autosomal dominant disease responsible for 1% of all strabismus cases and has been related to a 8q12-13 contiguous gene syndrome. We report on an insertion of chromosome region 8q13-q21.2 on to band 6q25 in a patient presenting with Duane syndrome, mental retardation, and other dysmorphisms. FISH analysis using chromosome 8 radiation hybrid LIA2L indicated a concurrent deletion within the 8q rearranged region. These results were corroborated by STR-PCR analysis and FISH using YAC contig WC8.8 disclosed a deletion in 8q13. Comparison of the two known patients with Duane syndrome associated with deletion of 8q identifies a small region of overlap (SRO) of < 3 cM extending from D8S533 and D8S1767 in which a Duane syndrome locus is assigned. In addition YAC analysis in our patient showed that 8q rearrangement was rather complex since 8q deletion and insertion occurred in two distinct segments separated by a region which maintained its location on 8q.

We report on a cytogenetic study of 100 subjects with Down syndrome (DS), diagnosed from 1980 to 1988, and their parents. Free trisomy was present in 95% of the patients; 5% had trisomy due to an unbalanced translocation. Approximately 60% of patients were born to mothers younger than age 35 years, the highest number of DS births being in the group of mothers between ages 25 and 29 years. These findings are clearly related to the higher number of pregnancies in this group. However, the prevalence of DS births increased significantly in women older than age 35 years, as expected. A cytogenetic study of heterochromatic polymorphisms showed a significant increase of polymorphisms in DS children and in their parents, mostly in mothers, compared with a control group. Since heterochromatic blocks of acrocentric and nonacrocentric chromosomes are frequently associated during interphase, we discuss a possible correlation between nondisjunction and heterochromatic polymorphism.

We describe the case of an adult patient affected by multiple exostoses, severe mental retardation, epilepsy and facial dysmorphisms with a deletion of ∼2.3 Mb on chromosome 11p11.21, correlated to Potocki-Shaffer syndrome (PSS). PSS is a rare contiguous gene deletion syndrome, mainly characterized by multiple exostoses and bilateral parietal foramina. Mental retardation and craniofacial dysmorphisms have often been reported, too. Although the patient showed many signs of PSS since early childhood, the diagnosis was suggested only when we examined her at adult age. This case highlights how frequently rare diseases remain undiagnosed till adulthood and is an excellent example of the need for a timely and correct diagnosis.

A fluorescence in situ hybridization (FISH) study was performed in 56 patients with short stature of unknown cause in order to establish the role of deletion of the SHOX gene in this population. FISH analysis was carried out on metaphase spreads and interphase lymphocytes from blood smears using a probe specific for the SHOX gene. Deletion of SHOX was found in four patients (7.1%). No skeletal abnormalities were detected in these patients either at the physical examination or at X-rays of the upper and lower limbs. Present results indicate that SHOX plays an important role also in short stature of unknown cause, and FISH analysis appears as an easy, appropriate, and inexpensive method for the detection of SHOX deletion.

Twelve patients with different features of Turner syndrome, and with Xp and Yp rearrangements involving the pseudoautosomal region (PAR1) are described. In all patients, FISH analysis showed loss of one copy of the Short Stature Homeobox (SHOX)-containing gene. Ten patients had short stature and one disproportionate (mesomelic) normal stature, while the last one had normal stature. Skeletal abnormalities, including shortened ulna, were detected in nine subjects, and in six of them Madelung deformity was observed. These clinical data indicated a genotype phenotype correlation between haploinsufficiency of SHOX, and short stature and skeletal abnormalities.

Authors report on a case of partial 9p duplication, involving the 9p22-9p24 region. This represents the second case of such duplication in which the breakpoints were precisely defined using fluorescence in situ hybridisation (FISH) with chromosome 9 specific painting and YAC DNA probes, localised onto 9p22-9p24 region. FISH analysis pinpointed chromosome breakpoints in dup(9)(p22p24) and excluded an insertion or a translocation from other chromosomes. The present report supports the segment 9p22-9p24 as the critical region for the observed phenotype of the duplication 9p syndrome.

A screening study performed on 2,803 pregnant women using the "triple test" is reported.Nine hundred and twenty-one had a high prior risk, having35 years while, after the screening, only 201 women had a positive test at risk higher than 1:270, and underwent to amniocentesis. The detection rate (DR) for all abnormalities was 91% while for Down's syndrome (DS) it was 87.5% and for neural tube defects 85.5%. Foetal abnormalities were detected in 20 cases (1:10) while 181 were false positive cases (6.5%), of which 151 for DS (5.4%). False negative were observed only in 2 cases within 2,339 at term pregnancies.The authors retain that high DR is related to the exactness of determination of gestation age calculated by scan and to the homogeneity of the examined population.

Cytogenetic investigations and molecular analysis of the Y chromosome by the polymerase chain reaction amplification of sequence-tagged sites (STS-PCR) technique were performed in 126 patients affected by idiopathic oligo-azoospermia following accurate selection of cases. Seventeen patients evidenced an abnormal karyotype. Fourteen patients with a normal karyotype had microdeletions of the Y chromosome within interval 6. In azoospermic patients microdeletions were scattered along different subintervals, while in oligozoospermic patients they were clustered in subinterval 6E. The size of the deletion was not apparently related to the severity of the disease. These results suggest that cytogenetic analysis and the STS-PCR technique can detect a genetic cause of infertility in about one-quarter of patients with idiopathic oligo-azoospermia.

Y chromosome molecular analysis was performed using the STS-PCR technique in 50 patients with oligozoospermia. Microdeletions of interval 6 of the Y chromosome were detected in seven patients, in six of whom subinterval E was affected. All patients retained the RBM1 and DAZ genes, while in one deletion involved the SPGY gene. The size of the deletion was not apparently related to the severity of the disease. These results suggest the presence of an oligozoospermia critical region on the Y chromosome within subinterval E of interval 6.

A liveborn female with a phenotype suggestive of Down syndrome is reported. Cytogenetic lymphocyte analysis showed a 46,X der(X) karyotype. Fluorescence in situ hybridization (FISH) with a biotinylated probe specific for chromosome 21 showed no signal on the der(X). This marker was homogeneously painted using a specific probe for X chromosome. In addition, FISH analysis detected telomeres on the rearranged X. Therefore, the proband's karyotype was reevaluated as 46,X,del(X) (pter-->p22.2::p11.3-->qter). Cytogenetic analysis of 150 lymphocytes in the mother disclosed a homogeneous 45,X karyotype. FISH analysis of interphase nuclei using the X chromosome painting probe showed two domains of different sizes in 0.8% of cells. This led us to study further metaphases in the mother. In one out of 450 metaphases scored, after FISH with the X chromosome painting probe, the del(X) was observed, confirming that the rearranged X chromosome found in the newborn had segregated from a 45,X/46,X,del(X) mother.

Two non-familial extra supernumerary abnormal chromosomes (ESAC) were detected in fetuses monitored by midtrimes ter amniocentesis. Characterization of these ESACs was carried out using conventional cytogenetic analysis, fluorescence in situ hybridization, and DNAse I hypersensitivity. Based on these studies it was concluded that the two ESACs were derived respectively from chromosomes 14/22 and isodicentric chromosome 15. Based on cytogenetic results it was argued that unconsistent phenotypic effect was associated with the two aneuploidies. This optimistic view was confirmed at birth of unaffected babies and unremarkable follow up at 6 and 12 months.

Five patients (age range 7-14 years) received allogeneic bone marrow transplantation (BMT) for Fanconi anemia (FA). All patients showed progressive pancytopenia associated with congenital malformations. Diagnosis was confirmed by studies of cellular hypersensitivity to the clastogenic effect of the DNA crosslinking agent diepoxybutane. The conditioning regimen consisted of low dose cyclophosphamide (5 mg/kg x 4) and fractionated total body irradiation (167 cGy x 3). For graft-versus-host disease prophylaxis one patient was given cyclosporin alone while the remaining four patients received a combination of cyclosporin and two doses of methotrexate. Marrow was given unmanipulated from HLA-identical siblings. All patients are alive 18-67 months after grafting with Karnofsky scores of 100% and normal hemopoiesis of donor origin. Modifications in transplant protocols such as those here described have resulted in a decreased risk of severe transplant-related complications. These results confirm that BMT is a curative therapy in FA patients and should be considered as a first choice treatment if an HLA-identical donor is available.

AluI and HaeIII restriction endonuclease banding patterns were analyzed in Macaca fuscata and Cercopithecus aethiops sabaeus chromosomes. AluI produced C-negative bands in both species of monkeys, while HaeIII induced the appearance of C-negative bands on Macaca chromosomes and of simultaneous G + C bands on Cercopithecus metaphases.

The authors report on a cytogenetic survey of 61 patients with preleukemic syndrome (PLS). Of these, 41 had a myeloproliferative disease (MPD) and 20 a myelodysplastic syndrome (MDS). Clonal chromosome abnormalities appeared in 24 patients (39.3%) at disease onset. Such changes had a frequency of 26.8% in patients with MPD and 65% in those with MDS. The authors stress the usefulness of ethidium bromide high resolution techniques. They allow obtaining a larger number of metaphases and elongated chromosomes with higher banding resolution and could account for the frequent detection of chromosome changes in most groups of MDS patients in the present series. Moreover, they discuss the possible significance of some chromosome aberrations suggesting that patients with MPD may live longer than those with MDS because of their higher frequency of normal karyotypes.

The authors report on the activity of Hinf I restriction endonuclease on human fixed metaphase chromosomes. Experiments performed by digesting chromosomes just after harvesting or after ageing in methanol-acetic acid displayed a different pattern of digestion on metaphases, since only aged preparations showed gaps on heterochromatic regions of chromosomes 1, 9 and 16 and C-like bands on other chromosomes. In this view, the authors suggest that structural modifications of the DNA, induced by acid fixation, can influence Hinf I activity on fixed metaphase chromosomes.

Height is the result of interactions of several factors including those of genetic origin. About 3% of people have short stature and in most of them the cause is unknown.1 Recently, the SHOX gene (short stature homeobox containing gene), mapped on the pseudoautosomal region (PAR1) of the X and Y chromosomes, has been specifically associated with the short stature of patients with Turner syndrome or with Leri-Weill dyschondrosteosis (LWD).2–7 Few data have been reported on the relationship between SHOX mutations and idiopathic short stature. Rao et al 2 reported one change among 91 patients with idiopathic short stature, and Binder et al 8 found a mutation in one out of 68 patients. The largest study was recently published by Rappold et al ,9 who found a frequency of 2.4% of SHOX mutations using fluorescence in situ hybridisation (FISH) on 150 patients and single strand conformational polymorphism analysis (SSCP) on 750 patients. We report a study carried out on 56 patients with short stature of unknown origin detecting SHOX mutations in seven (12.5%) by using FISH and direct sequencing analyses. ### Patients Fifty-six patients, 33 females and 23 males, with a mean age of 12.2 years (range 5-18 years) entered this study. All patients were unrelated, coming from different regions of central and southern Italy. In order to exclude patients with dyschondrosteosis or other diseases associated with short stature, we used the following criteria: (1) height at or below the 3rd centile; (2) absence of obvious skeletal abnormalities on physical examination; (3) absence of other diseases on physical examination and routine analyses; (4) normal bone age; (5) normal hGH values using a polyclonal in house RIA (lower detection limit 0.1 ng/μl, mean intra-assay coefficient of variation 6.9%, and mean interassay coefficient 9.5%); and (6) normal karyotype in 16 metaphases …

Alul and Haelll restriction endonuclease banding patterns were analyzed in Macacafuscata and Cercopithecus aethiops sabaeus chromosomes. AluI produced C-negative bands in both species of monkeys, while Haelll induced the appearance of C-negative bands on Macaca chromosomes and of simultaneous G + C bands on Cercopithecus metaphases.

We report on 19 patients with Waldenstrom's macroglobulinemia (WM) who were studied cytogenetically at the onset and during progression of the disease. We found a high frequency of chromosome changes confirming the claim of other authors that, during progresssion of the disease, a large number of residual neoplastic cells, insensitive to conventional chemotherapy, persist. In turn, this may be the cause of the difficulty of inducing remission (21% of cases) and of the short survival (mean, 35 months). In our experience it is difficult to identify the primary chromosome abnormalities because of the late clinical stage at which the chromosomes were examined. However, changes involving chromosomes #10, #11, and #12 may be unfavorable events in patients with WM.

Cytogenetic studies on a group of 140 patients with alterations of sex features (sex uncertainty, gynecomasty, menstrual abnormality and so on) confirmed a high incidence of chromosome abnormalities (25%). Most frequent abnormal kariotypes were X0 and XXY. Furthermore, cytogenetic investigations showed a higher rate of heterochromatic polymorphism in patients (33.7%) than in controls (13.4%), the most frequent being 1qh, 9qh and 16qh. A possible role of heterochromatic polymorphism in determining sex chromosome abnormalities or, directly, sex diseases, and in possibly enhancing neoplastic risk, is suggested.

The authors report haematologic and cytogenetic data from 47 patients with ANLL, demonstrating the usefulness of cytogenetic studies for the classification as well as for the prognosis of this disorder. Chromosome studies also permitted the classification of marrow cellularity in: all diploid metaphases (NN), diploid and aneuploid metaphases (AN), and all aneuploid metaphases (AA). The remission rate for patients in whom only normal metaphases were detected (NN patients) was 83% while the remission rates were 67% and 33% respectively for patients in whom both normal and abnormal metaphases were seen (AN patients) and for those in whom only abnormal metaphases were noted (AA patients). In all FAB subgroups, complete remission was related to chromosomal abnormalities, except for M4 patients who evidenced a large number of complete remissions, although presenting more chromosomal abnormalities. The longer survival in this subgroup may be related to rearrangements of chromosome 16, which is associated with a better prognosis.