Clinical and molecular studies in two families with Fraser syndrome: a new FRAS1 gene mutation, prenatal ultrasound findings and implications for genetic counselling.

Fraser syndrome is a rare autosomal recessive genetic disorder characterized by cryptophthalmus, variable expression of cutaneous syndactyly of fingers and toes, genital ambiguity and renal agenesis/dysgenesis. We present here molecular and clinical findings of four fetuses with FS from two families. Molecular genetic studies in the two families revealed mutations in FRAS1 gene allowing better genetic counselling and subsequent prenatal diagnosis in one of the two families. In family one, a nonsense mutation (c.3730C>T, p.R1244X) previously described in a Polish patient was found. In family two a novel nonsense mutation previously not known was detected (c.370C>T, p.R124X). PGD is planned for family 1.

Two cases of 9p deletion syndrome and a case of partial trisomy 8 and partial monosomy 9p.

Two cases of 9p deletion syndrome anda case of partial trisomy 8 and partial monosomy 9p: We report 3 girls with mental retardation (MR), distinctive malformations of the skull and facial region, including trigonocephaly, small palpebral fissures, and unusually midface hypoplasia, congenital heart defects which are characteristics of monosomy 9p. We performed GTG banding and fluorescence in situ hybridization (FISH) method in all cases. By using cytogenetic methods, three terminal deletions of the short arm of the chromosome 9 were identified and in 2 patients the deletion was de novo, and one patient inherited deletion. FISH analysis showed 46,XX,del(9)(pter-p22).ish del(9)(pter-->p22) in two patients and 46,XX,-9,+der(9)t(8;9)(q24.3;p22)pat.ish der(9)t(8;9)(q24.3;p22)pat (305J7-T7x1,wcp8+,wcp9+) in the third patient. This report compares the symptoms and features of our patients with previously reported patients with a 9p deletion syndrome.

Acute complete splenic infarction in a patient with Hirschsprung's disease and literature review of complete splenic infarction.

Here we report a case of Hirschsprung's disease presenting with acute complete splenic infarction due to thrombus in the splenic vena. MTHFR C677T (methylenetetrahydrofolate) gene homozygote mutation was a risk factor for thrombosis. According to our knowledge, this is the first report for a Hirschsprung's disease patient with acute complete splenic infarct due to isolated splenic vein thrombosis accompanied by MTHFR C677T gene homozygote mutation.

657del5 mutation in the NBS1 gene is associated with Nijmegen breakage syndrome in a Turkish family.

We report on a consanguineous Turkish family whose first son died of anal atresia and whose second son presented with severe pre- and post-natal growth retardation as well as striking microcephaly, immunodeficiency, congenital heart disease, chromosomal instability and rhabdomyosarcoma in the anal region. The proband was found to carry the homozygous 657del5 mutation in the NBS1 gene, which is responsible for Nijmegen breakage syndrome (NBS) in most of the Slav populations. Our family, the first diagnosed with NBS in the Turkish population, represents one of the most severely affected examples of the syndrome, with profound pre- and post-natal growth retardation associated with structural abnormalities, and expands the clinical spectrum of this rare disorder.

Therapy-related refractory anemia with ringed sideroblasts in chronic lymphocytic leukemia. involvement of 3q21 region.

Therapy-related myelodysplastic syndrome/acute myelogenous leukemia (t-MDS/AML) is extremely rare in chronic lymphocytic leukemia (CLL) despite extensive use of alkylating agents. We present a case of heavily treated CLL with resultant therapy-related refractory anemia with ringed sideroblasts (RARS). A complex cytogenetic abnormality including involvement of 3q21 was detected and to our knowledge, is the first report of a RARS case with a 3q21 abnormality.

Fusion of a novel gene, RCC17, to the TFE3 gene in t(X;17)(p11.2;q25.3)-bearing papillary renal cell carcinomas.

A subset of childhood and young adult renal cell carcinomas displays a recurrent translocation t(X;17)(p11;q25) as the sole cytogenetic abnormality. In two young girls, we demonstrate that this translocation results in the fusion of a novel gene, designated RCC17, at chromosome 17q25, to the transcription factor TFE3 located on the Xp11 chromosomal region. In both cases, the t(X;17) fuses the NH(2)-terminal region of RCC17 to the COOH-terminal part of TFE3 including the basic helix-loop-helix DNA-binding domain and the leucine zipper dimerization domain. The reciprocal fusion transcript TFE3/RCC17 is also expressed. RCC17 encodes a putative protein of 553 amino acids. It is ubiquitously expressed in normal adult tissues. No significant similarity was found with other fusion partners of TFE3 or with any relevant functional protein domains, precluding informed speculation about the normal function of this gene.

Severe intrauterine growth retardation, aged facial appearance, and congenital heart disease in a newborn with Johanson-Blizzard syndrome.

We report a female newborn with Johanson-Blizzard syndrome associated with extreme intrauterine growth retardation, aged facial appearance, and atrial septal defect. Other features are microcephaly, prominent veins over the scalp, alopecia over the vertex, wide-open fontanelle, high forehead, antimongoloid slant, edematous eyelids, the absence of eyebrows and eyelashes, beaked nose with alae nasi, low-set ears, thin lips, and micrognathia. Investigations revealed deafness and congenital hypothyroidism. We believe that this association of severe intrauterine growth retardation and congenital heart disease represents the components of this syndrome.

Impact of Fluorescence in Situ Hybridization in the Detection of Cryptic Fusion Transcript PML/RARA and A Complex t(5;15;17) in a Case of Acute Promyelocytic Leukemia.

Genetic aspects of a 28 year-old female patient with typical morphological and clinical features of acute promyelocytic leukemia is presented. Pml/rara fusion transcript and a complex translocation involving chromosomes 5, 15 and 17 were detected by fluorescence in situ hybridization (FISH) technique which was applied as in adjunct to conventional cytogenetics. The patient deceased soon in spite of the immediate ATRA and cytostatic therapy.

Phenotype-genotype correlation in familial Mediterranean fever: evidence for an association between Met694Val and amyloidosis.

Familial Mediterranean fever (FMF) is an autosomal recessive disease characterised by recurrent attacks of inflammation of serosal membranes. Amyloidosis is the most severe complication of the disease. The aim of this study was to investigate the genotype-phenotype correlation and specifically the association between amyloidosis and the four common mutations in exon 10 of the gene causing FMF (MEFV) in a total of 83 FMF families from three ethnic groups: North African Jews, Armenians and Turks. A significant association was found between amyloidosis and the specific mutation at the MEFV gene: Met694Val (RR = 1.41, P = 0.02). Amyloidosis was present in 18 out of 87 homozygous FMF patients (20.7%) and in only two out of the 41 compound heterozygous FMF patients (4.9%). No patients carrying other mutations had amyloidosis. There was no significant association between the various mutations and the type or severity of the FMF symptoms. This finding underscores the importance of performing molecular studies on all suspect FMF patients. In addition to providing accurate diagnosis, these tests allow identification of presymptomatic genetically affected individuals, detection of carriers and assessment of the risk for amyloidosis in later life.

Amyloidosis in familial mediterranean fever is associated with a specific ancestral haplotype in the MEFV locus.

Familial Mediterranean fever (FMF) is a recessive disease characterized by recurrent attacks of inflammation of serosal membranes, and the gene responsible, MEFV, has been recently identified. Amyloidosis is considered to be the most severe complication. Since colchicine is effective in preventing FMF amyloidosis and since this process can develop even prior to the FMF symptoms, lifelong colchicine treatment is recommended for all FMF patients. Identification of the factor which determines amyloidosis will allow treatment to be directed only to those at risk. In order to investigate the association between amyloidosis and MEFV haplotypes, we studied 56 families from three ethnic groups. We compared the haplotypes of FMF patients with and without amyloidosis in each ethnic group separately and identified 14 different MEFV core haplotypes. A significant association (P < 0.004) was found between amyloidosis and a specific core haplotype, 153bp:104bp at markers D16S3370 and D16S2617, respectively. Amyloidosis was present in 20 out of 70 homozygotes for this haplotype and in 6 out of 35 compound heterozygotes for this and other core haplotypes. None of the patients who did not carry this allele had amyloidosis. There was no association between the various haplotypes and severity of the FMF symptoms, age of onset, or age at commencement of colchicine. Further investigation of the MEFV haplotypes in additional patients is recommended as such an association may save many mildly affected or asymptomatic patients with non-amyloidotic genotypes from receiving unnecessary lifelong colchicine treatment.

Assessment of pyrin gene mutations in Turks with familial Mediterranean fever (FMF).

Familial Mediterranean fever (FMF) is an autosomal recessive disease clinically characterized by recurrent short self-limited attacks of fever accompanied by peritonitis, pleurisy, and arthritis and can lead to amyloidosis and renal failure in the longer term. It is prevalent mainly in non-Ashkenazi Jews, Armenians, Turks, and Arabs. Due to the lack of an accurate diagnostic test, patients often experience years of attacks and invasive diagnostic procedures before the correct diagnosis is made and adequate treatment is begun. Recently, the gene responsible for FMF, denoted pyrin, has been cloned, and three disease mutations have been described (French FMF Consortium, 1997; International FMF Consortium, 1997). In the current study we assessed the spectrum of mutations in this gene in 16 unrelated families of Turkish origin. The three previously reported missense mutations (Met-Ile at codon 680, Met-Val at codon 694, and Val-Ala at codon 726) accounted for 29 of the 34 disease alleles. In one patient in whom no disease mutation was identified, the clinical picture was atypical enough to raise questions regarding the diagnosis. These results imply that the origin of FMF in Turkey is heterogeneous, that molecular diagnosis of FMF is possible in the majority of cases and clinically helpful, and that delineation of the undiscovered disease mutation(s) in the remaining cases remains a high priority.

The deltaccr5 mutation conferring protection against HIV-1 in Caucasian populations has a single and recent origin in Northeastern Europe.

The chemokine receptor CCR5 is encoded by the CMKBR5 gene located on the p21.3 region of human chromosome 3, and constitutes the major co-receptor for the macrophage-tropic strains of HIV-1. A mutant allele of the CCR5 gene, Delta ccr5 , was shown to provide to homozygotes with a strong resistance against infection by HIV. The frequency of the Delta ccr5 allele was investigated in 18 European populations. A North to South gradient was found, with the highest allele frequencies in Finnish and Mordvinian populations (16%), and the lowest in Sardinia (4%). Highly polymorphic microsatellites (IRI3.1, D3S4579 and IRI3.2, D3S4580 ) located respectively 11 kb upstream and 68 kb downstream of the CCR5 gene deletion were used to determine the haplotype of the chromosomes carrying the Delta ccr5 variant. A strong linkage disequilibrium was found between Delta ccr5 and specific alleles of the IRI3.1 and IRI3.2 microsatellites: >95% of the Delta ccr5 chromosomes carried the IRI3.1-0 allele, while 88% carried the IRI3.2-0 allele. These alleles were found respectively in only 2 or 1.5% of the chromosomes carrying a wild-type CCR5 gene. From these data, it was inferred that most, if not all Delta ccr5 alleles originate from a single mutation event, and that this mutation event probably took place a few thousand years ago in Northeastern Europe. The high frequency of the Delta ccr5 allele in Caucasian populations cannot be explained easily by random genetic drift, suggesting that a selection advantage is or has been associated with homo- or heterozygous carriers of the Delta ccr5 allele.

del(17)(q25) in a patient with hairy cell leukemia: a new clonal chromosome abnormality.

Clonal chromosomal aberrations are reported in about 25% of the patients with hairy cell leukemia (HCL). No consistent cytogenetic abnormality has been described in HCL; most of the chromosomal changes found have been deletions and inversions, with the rare occurrence of translocations. While most of the chromosomal aberrations in HCL are common to the ones found in B cell chronic lymphocytic leukemia and other B cell lymphoproliferative disorders, there are also certain chromosomal changes that are not found in other B cell lymphoproliferative disorders. We present here a 63-year-old male patient with hairy cell leukemia with the clonal del(17)(q25), which has not previously been reported in HCL.

Variable clinical expression of Holt-Oram syndrome in three generations.

Holt-Oram syndrome is a distinct autosomal dominant entity presenting with upper limb defects and cardiac abnormality. No correlation between the severity of the heart and the limb defects has been established. Here we report variable clinical expression of Holt-Oram syndrome in three generations. The grandfather presented with typical upper limb defects: phocomelia of arms with three digits on each hand, congenital heart defect and narrow shoulders. His son manifested cardiac conduction disturbance with no congenital heart or skeletal defect. The granddaughter showed ventricular septal defect and moderate radial deviations of both hands with no obvious hypoplasia of the extremities. Clinical data of the presented family suggests lack of penetrance with respect to skeletal and structural cardiac abnormalities in the Holt-Oram syndrome.

Application of the 'Apt test' in prenatal diagnosis to evaluate the fetal origin of blood obtained by cordocentesis: results of 30 pregnancies.

This study aimed to set up a practical lab-side approach to discriminate fetal from maternal blood in samples obtained by cordocentesis. To determine the fetal origin of the blood, a modified Apt test was applied to 30 cases of prenatal diagnosis. A change of colour of the fetal and adult blood during the procedure was the hallmark to assess fetal origin. At the end of 60 s of the test, fetal blood yielded a pink colour whereas adult blood was dark green-brown. The test was repeated in mixtures of fetal and adult blood. The results suggest that the modified Apt test is a practical, quick, inexpensive, and efficient test to determine the origin of blood samples obtained by cordocentesis. However, it should be kept in mind that samples containing a mixture of both fetal and adult blood could also yield a fetal blood reaction. When maternal contamination is suspected, we propose that at least 30 metaphases from different slides should be counted. This could yield fetal as well as maternal chromosomes.

Clinical and cytogenetic studies of two cases of Klinefelter syndrome with hereditary retinoblastoma and rhabdomyosarcoma.

Two children with Klinefelter syndrome (KS), one associated with bilateral hereditary retinoblastoma (RB) and the other with rhabdomyosarcoma (RMS) are reported. Both were boys and chromosomally mosaic for KS. The hereditary retinoblastoma case yielded 46,XY,del(13)(q12q14.2)/47, XXY(c),del(13)(q12q14.2) in PHA-stimulated lymphocytes. The rhabdomyosarcoma case yielded 46,XY/ 47,XXY(c) in peripheral blood cells whereas tumor revealed trisomy 8, trisomy 7, and t(7;13)(q33;q32) in addition to 46,XY/47,XXyc mosaicism.

Multiple clonal chromosome aberrations in a case of childhood focal nodular hyperplasia of the liver.

A case of focal nodular hyperplasia is described that was accompanied by intense reactive stromal changes giving rise to a pseudosarcomatous appearance. Cytogenetic study revealed complex karyotypic abnormalities including five partially identifiable clonal aberrations and one marker chromosome. The composite karyotype was interpreted as: 45-46,XY,add(4)(q21-25)[24], add(11)(p14)[24], add (19)(p13)[15], der(20)t(1;20)(q25;p12)[31], add(21) (q22)[13],-22[3], +mar[2][cp31]. In addition, quadriradial or complex figures, telomeric associations tas, unidentified ring chromosomes, chromosome breaks, and markers were seen in some cells. Such cytogenetic findings, although suggestive of malignancy, could most likely be related to a nonneoplastic condition, i.e., the unusual florid reactive changes associated with this focal nodular hyperplasia.

A new deletion of the 5 alpha-reductase type 2 gene in a Turkish family with 5 alpha-reductase deficiency.

UNLABELLED: The molecular basis for male pseudohermaphroditism produced by the 5 alpha-reductase deficiency is becoming increasingly understood. OBJECTIVE: We have performed biochemical and molecular analyses of the 5 alpha-reductase type 2 gene in a Turkish family with a 5 alpha-reductase deficiency. PATIENT: A 46,XY prepubertal Turkish patient with female phenotype showing clitoral hypertrophy, high plasma testosterone and dihydrotestosterone, and normally differentiated and developed testosterone-dependent internal genitalia. MEASUREMENTS: 5 alpha-Reductase activity, measured by the conversion of 3H-T into 5 alpha-reduced compounds, was determined from cultured genital skin fibroblasts by both intact monolayer assay and cell-free extracts at various pH values. The five exons of the 5 alpha-reductase type 2 gene were sequenced after enzymatic amplification (PCR) of the patient's genomic DNA. Labelled PCR of the consanguineous parents' DNA was submitted to electrophoresis on a sequencing gel. RESULTS: A marked decrease in the transformation of T into 5 alpha-reduced compounds by intact cells and a diminished 5 alpha-reductase activity at acidic pH by sonicated cell extracts strongly suggested a 5 alpha-reductase type 2 deficiency. Molecular analysis of the 5 alpha-reductase type-2 gene showed a trinucleotide deletion straddling codons 156 and 157, responsible for a methionine residue deletion at position 157 of the protein. The parents' DNA contained both normal and deleted alleles. CONCLUSIONS: This is the third deletion described in the 5 alpha-reductase type 2 gene. The deleted methionine 157 is conserved in both types 1 and 2 of human and rat 5 alpha-reductase, which suggests its crucial role in the functioning of the enzyme. This gene rearrangement was thus clearly responsible for the reduced 5 alpha-reductase activity and abnormal genital development in this patient.

Prenatal diagnosis of autosomal recessive osteopetrosis, infantile type, by X-ray evaluation.

Prenatal diagnosis for infantile osteopetrosis was attempted during the third pregnancy of a first-cousin marriage whose family history revealed an affected previous child. At the 25th week of pregnancy, fetal X-ray evaluation revealed marked sclerosis of osteopetrotic bone and metaphyseal splaying and clubbing of both femurs. The pregnancy was terminated and repeated X-rays and histopathological examination of fetal bone (femur) confirmed the diagnosis.