Cytogenetic effects of ethanol on chronic alcohol users

AIM

Alcoholism is a significant public health problem that is also associated with a complex genetic trait. Fragile sites (FS) are potentially informative endpoints for the study of clinical disorders. We aimed to find chromosomal damages in chronic alcohol users for the purpose of finding the correlation between alcohol and chromosomal anomalies.

METHODS

The potential roles/effects of ethanol on chromosome(s) were assessed in this study by investigating its cytotoxic effects in lymphocyte cultures from chronic alcoholics and controls.

RESULTS

Alcoholics revealed a significantly higher frequency of FS and chromosomal aberrations (CA), and the FS clusters in specific chromosomal regions: 1q12, 1q21, 1q32, 2p13, 2q21, 2q31, 3p14, 3p25, 3q21, 4q21, 4q31, 5q31, 6p21, 7q22, 7q32, 9q13, 9q22, 10q22, 11q23, and 12q13. We also observed a significantly greater number of numerical and structural CA in alcoholics. The most frequent exchange types were deletions and polymorphic variations. CA could be due to the cumulative effect of both alcohol and smoking. The loci 1q12, 3p25, 4q31, 6p21, and 12q13 were not reported previously in alcoholics and may be hot spots for alcoholism. The overall FS frequencies were not statistically different between smoker and non-smoker controls, but smoking significantly increased the expression of 1p36, 3q21, and 5p15 sites. These sites have important clinical significance.

CONCLUSIONS

Chronic alcohol abuse and the smoking habit can lead to chromosome damages that are especially influential on oncogenic regions, which may persist for a long time, and constitute a relevant factor of risk for the development of neoplasias.

Inheritance of a translocation between chromosomes 12 and 16 in a family with recurrent miscarriages and a newborn with Down syndrome carrying the same translocation

Reciprocal translocation carriers have reduced fertility, increased risk of spontaneous abortion or unbalanced karyotype in their offspring. Here, we report the inheritance of a translocation between chromosomes 12 and 16 in a family with recurrent miscarriages and a newborn with Down syndrome carrying the same translocation. Chromosomal analysis from fetal amniotic fluid and peripheral blood lymphocytes from the family were performed at the Cukurova university hospital in Turkey. We assessed a family in which the translocation between chromosomes 12 and 16 segregates; one of the eight progenies with the karyotype 47,XY,+21,t(12;16)(q24;q24) was heterozygote for the translocation and presented with Down syndrome. His mother is phenotypically normal, one brother and one sister were also carrying the same translocation. Apparently, this rearrangement occurred due to the unbalanced chromosome segregation of the mother [t(12;16)(q24;q24)mat]. This case will enable us to explain the behavior of segregation patterns and the mechanism for each type oftranslocation from carrier to carrier and their effects on reproduction and numerical aberrations. The t(12;16) is also associated with fetal wastage and may play a role in the etiology of the family's miscarriages. These findings can be used in clinical genetics and may be used as an effective tool for reproductive guidance and genetic counseling.

Inheritance of pericentric inversion in chromosome 7 through the three progenies and a newborn with congenital hydronephrosis diagnosed prenatally by fetal urine sampling

OBJECTIVE

To report the inheritance of a pericentric inversion in chromosome 7 through the three progenies, congenital hydronephrosis, and recurrent miscarriages in an extended family.

DESIGN

Case report.

SETTING

Medical Faculty of Cukurova University in Turkey.

PATIENT(S)

Referred by obstetrics and gynecology clinic.

INTERVENTION(S)

Fetal urine and lymphocytic karyotype.

MAIN OUTCOME MEASURE(S)

Chromosomal analysis from fetal urine and peripheral blood lymphocytes were performed according to standard cytogenetic methods.

RESULT(S)

We assessed an extended family in which a large pericentric inversion in chromosome 7 is segregating; one of the three progenies with the karyotype 46,XY,inv(7)(p22;q22) was heterozygote for the inversion and presented with congenital hydronephrosis. His mother, mother's brother, grandfather, grandfather's brother, and his daughter were similar for the inversion.

CONCLUSION(S)

This case describes the further molecular characterization of these breakpoints on the short or long arm of chromosome 7(p22-q22). The inv(7) is also associated with fetal wastage and may be playing a role in the etiology of the family's miscarriages. These findings can be used in clinical genetics and may be an effective tool for reproductive guidance and genetic counseling.

Cytogenetic study of recurrent miscarriages and their parents

There are substantial evidences that genetic alterations are contributing factors to the risk for recurrent miscarriages. This study was conducted to determine the frequency and contribution of chromosomal abnormalities in miscarriages and in couples with recurrent miscarriages. We studied a total of 41 miscarriages and their parents with a history of 2-11 recurrent miscarriages. Chromosomal analysis from chorionic villus sampling (CVS) and fetal tissues were performed according to standard cytogenetic methods using G-banding technique. Major chromosomal aberrations and polymorphic variants were found in 51 and 4.8%, respectively. The chromosomal abnormalities were structural (34.4%) and numerical (65.1%) of which 26.1, 21.7, 8.7 and 8.7% were fetal sex aneuploid, triploid, mosaics and trisomic, respectively. Unbalanced and balanced rearrangements were found in 17.2% and 8.6% of all abnormalities, respectively. Major chromosomal abnormalities in couples were seen in 4.9%. The chromosomal abnormalities associated with pregnancy losses and recurrent miscarriages are mostly numerical ones. The incidence of balanced translocations found here is 4.9% which is near to the mode (about 3-6%) observed in the previous studies. Those frequencies are greater than in the general population (0.3%). This indicates that balanced translocations, seen in parents, have some importance in causing miscarriage. The major parental chromosomal aberrations are significantly associated with fetal wastage. Mosaicism should be taken into account for cytogenetic analyses of pregnancy losses. Thus, cytogenetic analyses should be recommended in couples with recurrent miscarriages, when clinical data fail to clarify the cause.

Chromosomal fragile site expression in Turkish psychiatric patients

Chromosomal aberrations associated with psychiatric disorders may suggest regions in which to focus a search for genes predisposing to psychosis by a linkage strategy. Identification of these may be especially important given the unknown pathophysiology and the probable genetic heterogeneity of psychiatric disorders. In this study, the frequencies of folate sensitive fragile sites (FS) were compared among psychiatric disorders (e.g., schizophrenia, bipolar disorder, and other psychosis) and normal individuals. The rate of FS expression in the patients was considerably higher than in the controls. Sites 1p22, 1q21, 1q32, 2q31, 3p14, 3p25, 5q22, 5q31, 6p21, 6q21, 6q25, 7q22, 7q32, 8q22, 10q21, 11q23, 12q24, 13q32, 14q24, 16q22, 17q21, Xp22 and Xq26 were expressed more frequently in the patients. Thirty possible relevant chromosomal sites were identified in schizophrenia: 1q21, 1q32, 2p13, 2q21, 3p14, 3p25, 3q21, 5q22, 5q31, 6p21, 6q25, 6q26, 7q21, 7q22, 7q32, 8q22, 9q21, 10q21, 11q23, 12q24, 13q32, 14q24, 16q22, 17q21, Xp22, Xq22, and Xq26. Possible relevant sites were also identified in bipolar disorder: sites 1p36, 1q21, 1q32, 3p14, 3p25, 5q31, 7q22, 7q32, 11q23, 12q24, 13q32, 14q24, Xp22, and Xq26. Sites in the other psychosis group were: 1p22, 1p32, 1p36, 1q21, 1q32, 2q31, 3p14, 3p25, 5q31, 6p21, 6q21, 6q25, 6q26, 7q22, 7q32, 8q22, 10q21, 11q23, 12q13, 12q24, 13q32, 16q22, 16q24, 17q21 and Xq26. Among patient groups, there were significant differences in bands 1p32, 2p13, 2q21, 2q31, 3p14, 3p25, 5q31, 6q21, 6q26, 7q22, 7q32, 9q21, 11qq23, 12q13, 12q24, 16q24, and Xq22 between schizophrenic and bipolar patients. These regions were more frequently expressed in schizophrenic patients than in bipolar patients. The 1p22, 1p32, and 16q24 regions were significantly more frequently expressed in the other psychosis group than in the bipolar group. These interesting regions, which may harbor important genes for psychosis, have produced strong support for linkage in the majority of genome scan projects.

A homozygous BMPR1B mutation causes a new subtype of acromesomelic chondrodysplasia with genital anomalies

We present a patient with acromesomelic chondrodysplasia and genital anomalies caused by a novel homozygous mutation in BMPR1B, the gene coding for bone morphogenetic protein receptor 1B. The 16 year old girl, the offspring of a multiconsanguinous family, showed a severe form of limb malformation consisting of aplasia of the fibula, severe brachydactyly, ulnar deviation of the hands, and fusion of carpal/tarsal bones. In addition, she presented with hypoplasia of the uterus and ovarian dysfunction resulting in hypergonadotrophic hypogonadism. Mutation analysis of BMPR1B revealed a homozygous 8 bp deletion (del359-366). This mutation is expected to result in a loss of function and is thus different from the heterozygous missense mutations in BMPR1B recently shown to cause brachydactyly type A2 through a dominant negative effect. The patient's skeletal phenotype shows an overlap with the clinical spectrum of the acromesomelic chondrodysplasias of the Grebe, Hunter-Thompson, and DuPan types caused by homozygous mutations in the gene coding for growth differentiation factor 5 (GDF5) which is a high-affinity ligand to BMPR1B. However, the phenotype described here differs from GDF5 associated chondrodysplasias because of the additional presence of genital anomalies and the distinct limb phenotype.

Partial trisomy 1p due to paternal t(1;9) translocation in a family with recurrent miscarriages

OBJECTIVE

To report a new case with partial trisomy 1p due to paternal t(1;9) translocation in a family with recurrent miscarriages.

DESIGN

Case report.

SETTING

Faculty of Medicine, Cukurova University.

PATIENT(S)

A couple with recurrent miscarriages, an abnormal fetus, a newborn infant, paternal grandfather and grandmother.

INTERVENTION(S)

Chorionic villi sampling (CVS), amniocentesis, lymphocytic karyotype, and genetic counseling.

MAIN OUTCOME MEASURE(S)

Chromosomal analysis of CVS, amniotic cells, and peripheral blood lymphocytes were performed according to standard cytogenetic methods using G-banding technique.

RESULT(S)

We determined the reproductive risk in a couple who carried a balance and an unbalanced rearrangement of chromosomes 1 and 9 in two generations of a normal father with derivative 9 karyotype. The prenatal and postnatal karyotypes of the newborn infant were the same as the father [46,XY,der(9)t(1:9)(p34.2;q34.3)]. He was also phenotypically normal. The abnormal fetus that was miscarried also had a derivative 9 [46,XY,der(9)t(1:9)(p34.2;q34.3)fat]. The der(9) contained the partial short arm of chromosome 1. Both chromosome 1 showed normal. Trisomy 1p in the fetus was the result of familial derivative 9.

CONCLUSION(S)

Partial trisomy is associated with fetal wastage, and may play a role in the etiology of the other miscarriages in certain families. The apparent lack of increased reproductive failure may result from the selective disadvantage of aneusomic gamets at fertilization or very early spontaneous abortions of unbalanced conceptuses. The detection of couples with chromosomal anomalies can undoubtedly help prevent the births of malformed infants. These findings would be used widely in clinical genetics and as an effective tool for genetic counseling and reproductive guidance.

Chromosomal fragile sites in schizophrenic patients

Schizophrenia is a common and complex mental disorder. Cytogenetic and molecular studies have shown that genetic factors play an important role in the etiology of schizophrenia. As a preliminary step in the search for chromosomal location of a susceptible gene predisposing to schizophrenia, cytogenetic screening patients might be useful. Therefore, this report is aimed at studying the relationship between chromosomal fragile sites (FS: gaps, breaks, triradial figures, and several rearrangements) and the etiology of schizophrenia. Because of this, we were compared the frequencies of folate-sensitive FS from schizophrenic patients and normal individuals in short-term whole blood cultures. The rate of FS expression in the patients was considerably higher than in the controls. We determined 15 common FS (cFS) (1q21, 1q32, 2q21, 2q31, 3p14, 4q31, 5q31, 6q21, 6q26, 7q22, 7q32, 10q22, 13q32, Xp22 and Xq22), 6 rare FS (rFS) (6p21, 8q22, 11q23, 12q24, 16q22, and Xq26) and 2 previously unknown FS (3p25 and 5q22). Among these expressed FS, there was a significantly higher frequency of 12 FS at 2q31, 3p25, 3p14, 5q31, 6q21, 7q22, 7q32, 10q22, 11q23, 12q24, Xq22 and Xq26 in patient group than in controls by chi2 test (P = between 0.0001 to 0.036). Sites 3p14, 5q31 and 7q22 were also the most frequently observed cFS. Males exhibited twice as many FS as females, but no age effects were observed. The potential relationship between increased FS frequency and the occurrence of schizophrenia in these patients is discussed.

Cerebellar hypoplasia and quadrupedal locomotion in humans as a recessive trait mapping to chromosome 17p

BACKGROUND

Congenital hereditary non-progressive hypoplasia of the cerebellum is a rare condition, frequently associated with other neuropathology such as lissencephaly. Clinically, the condition is associated with variable degrees of mental retardation, microcephaly, seizures, and movement disorders due to ataxia. In severe cases, patients are unable to ambulate independently, but nevertheless do use bipedal locomotion.

METHODS AND RESULTS

Here we present a family with seven affected members, five of whom never learned to walk on two legs but have fully adapted to quadrupedal palmigrade locomotion. These subjects show signs of cerebellar ataxia and are mentally retarded. MRI analysis demonstrated hypoplasia of the cerebellum and the cerebellar vermis as well as a small nucleus dentatus and a thin corpus callosum but no other malformations. We show, by a genome-wide linkage scan, that quadrupedal locomotion is a recessive trait linked to chromosome 17p.

CONCLUSIONS

Our findings have implications for understanding the neural mechanism mediating bipedalism, and, perhaps, the evolution of this unique hominid trait.

Delayed onset bleomycin-induced pneumonitis

We describe a 39-year-old male patient who developed bleomycin-induced pneumonitis 2 years after completion of chemotherapy for nonseminomatous testicular cancer. Bleomycin sometimes causes fatal pulmonary toxicity, including bleomycin-induced pneumonitis. The central event in the development of pneumonitis is endothelial damage of the lung vasculature due to bleomycin-induced cytokines and free radicals. Pulmonary toxicity usually begins at bleomycin administration. The development of bleomycin-induced pneumonitis up to 6 months after bleomycin therapy has also been reported. We report a patient who developed bleomycin-induced pneumonitis 2 years after the initiation of bleomycin-containing chemotherapy regimens.

Chromosome aberrations in a schizophrenia population

Cytogenetic abnormalities with schizophrenia may provide a valuable clue to the identification of target loci and successful search for major genes. We have performed chromosomal examinations by using the GTG banding technique on 134 schizophrenics. In 43 patients (32%), random numerical and structural aberrations were detected. Structural aberrations predominated and usually consisted of deletions and inversion of various chromosomes. Numerical changes were present in one or two cells in 14 cases including trizomy 21, marker and acentric chromosomes, and 47,XXY. The seven cases with pericentric inversion and enlargement of the heterochromatin region of chromosome 9 (inv(9); 9qh+) were observed in the study. The incidence (5.2%) of inv(9) and 9qh+ in our schizophrenic patients were found higher than the general population, suggesting that a susceptibility locus for schizophrenia may be located at pericentromeric region of chromosome 9. Our study have detected 1q21, 7q23, inv(9), 9qh+, 11q23, 21q22, 22q11-13 and Xp11-q13 suggested that these chromosomal lesions are prevalent in schizophrenics. The reason for this might be that these anomalies increase risk for schizophrenia in a relatively nonspecific way, such as contributing to disruption of normal embryogenesis of the nervous system.

A cytogenetic study in 120 Turkish children with intellectual disability and characteristics of fragile X syndrome

We review the evidence for the frequency of the fragile X syndrome (FXS), other X-linked abnormalities, and other chromosomal disabilities of Turkish pediatric psychiatry outpatients with intellectual disability. Reported clinical features and genetic findings were used in cytogenetic screenings to estimate the prevalence of the fragile X (fra X) and other chromosomal aberrations in 120 patients with mental retardation, language disorders, attention deficit hyperactivity, or developmental delay, in comparison with 30 healthy children. Data on the clinical, intellectual and behavioral findings in 14 fra X positive children (11.7%) is presented. Ten of the 120 patients (8.3%) had enlargement of the heterochromatin region of chromosome 9. Other chromosomal aberrations and autosomal fragile sites (FS) were also observed. There was a statistically significant difference in the autosomal and X-linked FS between the study and control groups (p < 0.05). The tests for the fra X chromosome are likely to be of diagnostic benefit in young children with autism or developmental delay, particularly in speech, and who have large and prominent ears.

Identification of two different mutations in the PDS gene in an inbred family with Pendred syndrome

Recently the gene responsible for Pendred syndrome (PDS) was isolated and several mutations in the PDS gene have been identified in Pendred patients. Here we report the occurrence of two different PDS mutations in an extended inbred Turkish family. The majority of patients in this family are homozygous for a splice site mutation (1143-2A-->G) affecting the 3' splice site consensus sequence of intron 7. However, two affected sibs with non-consanguineous parents are compound heterozygotes for the splice site mutation and a missense mutation (1558T-->G), substituting an evolutionarily conserved amino acid. The latter mutation has been found previously in two Pendred families originating from The Netherlands, indicating that the 1558T-->G mutation may be a common mutation.

A case of spondylocostal dysostosis with a fra (5) (q32)

Spondylocostal dysostosis is a rare hereditary syndrome with various costal and vertebral deformities. No chromosomal abnormalities in connection with this syndrome were previously reported in literature. We report a case with spondylocostal dysostosis and chromosomal abnormality [fra (5) (q32)].

Results of cytogenetic investigation in adolescent patients with primary or secondary amenorrhea

A cytogenetic study of 77 adolescent girls with primary or secondary amenorrhea was performed. A pathologic or male karyotype was found in 18 (26.4%) of 68 patients with primary amenorrhea. In 1 (11.1%) of 9 patients with secondary amenorrhea, 46,XX/47,XXX mosaicism was recovered. The importance of the cytogenetic investigations in patients with primary or secondary amenorrhea was discussed.

The gene for Pendred syndrome is located between D7S501 and D7S692 in a 1.7-cM region on chromosome 7q

Pendred syndrome is an autosomal recessive disorder characterized by goiter and congenital deafness. The primary defect is not yet known, although the gene causing Pendred syndrome has been localized very recently on chromosome 7q, a region that also contains a gene responsible for nonsyndromal hearing loss (DFNB4). We confirmed linkage to this chromosome 7 region in five Pendred families originating from different ethnic groups, with a highest cumulative lod score of 8.26 for marker D7S501. In combination with previous reports, our results define a candidate region for the Pendred gene of 1.7 cM flanked by markers D7S501 and D7S692.

Bloodfeeding behavior of Anopheles sacharovi in Turkey

The feeding habits of Anopheles sacharovi under natural conditions and in feeding rooms were investigated by use of the gel diffusion technique. Mosquitoes were collected from various villages of Cukurova and also from feeding rooms especially prepared for these experiments. Human, cow, sheep, chicken, horse, and donkey were used as hosts in these rooms. The results showed that An. sacharovi is a zoophilic species. The females preferred donkey when human, cow, sheep, chicken, and horse were equally available. Their preference changed to horse, cow, and sheep in the absence of donkey. The host preference index (HPI) was always smaller than 1 for humans in habitats offering a choice of hosts. The human blood index was high only in human dwellings. In other habitats numbers of mosquitoes feeding on animals were higher than on humana. Although the human blood index was low, An. sacharovi is the principal human malaria vector in Turkey partly because a significant proportion of those resting in human dwellings have fed upon the occupants, and partly because of the uneven distribution of human and animal hosts.

Development of Plasmodium vivax in Anopheles superpictus under experimental conditions

The susceptibility of Anopheles superpictus for Plasmodium vivax was described quantitatively under laboratory conditions. Of the 697 laboratory females studied in 16 groups, 513 (73.5%) females took a bloodmeal, of which 88.4% developed ookinetes on day 1, 56.1% oocysts between days 3 and 11, and 52.5% sporozoites in the salivary gland on days 15 to 63 post-infection. Sporogony was completed in 10-11 days post-infection. There was no difference in the longevity of uninfected and infected females. Infected females survived an average of 30 days (maximum 63 days). Sporozoites survived up to 50 days in the salivary glands without any observable changes in structure and motility. These data indicate that An. superpictus is an efficient laboratory vector of P. vivax and should not be ignored in future entomological field studies.