Functional morphology and patterns of blood flow in the heart of Python regius

Brightness‐modulated ultrasonography, continuous‐wave Doppler, and pulsed‐wave Doppler‐echocardiography were used to analyze the functional morphology of the undisturbed heart of ball pythons. In particular, the action of the muscular ridge and the atrio‐ventricular valves are key features to understand how patterns of blood flow emerge from structures directing blood into the various chambers of the heart. A step‐by‐step image analysis of echocardiographs shows that during ventricular diastole, the atrio‐ventricular valves block the interventricular canals so that blood from the right atrium first fills the cavum venosum, and blood from the left atrium fills the cavum arteriosum. During diastole, blood from the cavum venosum crosses the muscular ridge into the cavum pulmonale. During middle to late systole the muscular ridge closes, thus prohibiting further blood flow into the cavum pulmonale. At the same time, the atrio‐ventricular valves open the interventricular canal and allow blood from the cavum arteriosum to flow into the cavum venosum. In the late phase of ventricular systole, all blood from the cavum pulmonale is pressed into the pulmonary trunk; all blood from the cavum venosum is pressed into both aortas. Quantitative measures of blood flow volume showed that resting snakes bypass the pulmonary circulation and shunt about twice the blood volume into the systemic circulation as into the pulmonary circulation. When digesting, the oxygen demand of snakes increased tremendously. This is associated with shunting more blood into the pulmonary circulation. The results of this study allow the presentation of a detailed functional model of the python heart. They are also the basis for a functional hypothesis of how shunting is achieved. Further, it was shown that shunting is an active regulation process in response to changing demands of the organism (here, oxygen demand). Finally, the results of this study support earlier reports about a dual pressure circulation in Python regius. J. Morphol., 2009. © 2008 Wiley‐Liss, Inc.     

Partial trisomy 4(q31qter) due to maternal 4;5 balanced translocation in a neonate

We describe a male neonate with a duplication of 4(q31.3qter) due to unbalanced segregation of a maternal translocation (4;5)(31.3;p15.1). He has a high broad nasal bridge, large, low-set ears, epicanthal folds, long philtrum, retrognathia, high arched palate, wide-spaced nipples, bilateral single transverse palmar creases, bilateral clinodactyly of the fifth finger, right cryptorchidism, and ventricular and secundum type atrial septal defect.     

Age-related maculopathy: a genomewide scan with continued evidence of susceptibility loci within the 1q31, 10q26, and 17q25 regions

Age-related maculopathy (ARM), or age-related macular degeneration, is one of the most common causes of visual impairment in the elderly population of developed nations. In a combined analysis of two previous genomewide scans that included 391 families, containing up to 452 affected sib pairs, we found linkage evidence in four regions: 1q31, 9p13, 10q26, and 17q25. We now have added a third set of families and have performed an integrated analysis incorporating 530 families and up to 736 affected sib pairs. Under three diagnostic models, we have conducted linkage analyses using parametric (heterogeneity LOD [HLOD] scores under an autosomal dominant model) and nonparametric (Sall statistic) methods. There is ongoing evidence of susceptibility loci within the 1q31, 10q26, and 17q25 regions. If we treat the third set of families as a replication set, then two regions (10q26 and 17q25) are replicated, with LOD scores >1.0. If we pool all our data together, then four regions (1q31, 2q14.3, 10q26, and 17q25) show HLOD or Sall scores > or =2.0. Within the 1q31 region, we observed an HLOD of 2.72 (genomewide P=.061) under our least stringent diagnostic model, whereas the 17q25 region contained a maximal HLOD of 3.53 (genomewide P=.007) under our intermediate diagnostic model. We have evaluated our results with respect to the findings from several new independent genomewide linkage studies and also have completed ordered subset analyses (OSAs) with apolipoprotein E alleles, smoking history, and age at onset as stratifying covariates. The OSAs generate the interesting hypothesis that the effect of smoking on the risk of ARM is accentuated by a gene in the 10q26 region--a region implicated by four other studies.     

Association between variants on chromosome 4q25, 16q22 and 1q21 and atrial fibrillation in the Polish population

Background

Genome-wide studies have shown that polymorphisms on chromosome 4q25, 16q22 and 1q21 correlate with atrial fibrillation (AF). However, the distribution of these polymorphisms differs significantly among populations.

Objective

To test the polymorphisms on chromosome 4q25, 16q22 and 1q21 in a group of patients (pts) that underwent catheter ablation of AF.

Methods

Four hundred and ten patients with AF that underwent pulmonary vein isolation were included in the study. Control group (n = 550) was taken from healthy population, matched for age, sex and presence of hypertension. All participants were genotyped for the presence of the rs2200733, rs10033464, rs17570669, rs3853445, rs6838973 (4q25), rs7193343 (16q22) and rs13376333 (1q21) polymorphisms.

Results

All the polymorphisms tested (except rs17570669) correlated significantly with AF in univariate analysis (p values between 0.039 for rs7193343 and 2.7e-27 for rs2200733), with the odds ratio (OR) 0.572 and 0.617 for rs3853445 and rs6838973, respectively (protective role) and OR 1.268 to 3.52 for the other polymorphisms. All 4q25 SNPs tested but rs3853445 were independently linked with AF in multivariate logistic regression analysis. In haplotype analysis six out of nine 4q25 haplotypes were significantly linked with AF. The T allele of rs2200733 favoured increased number of episodes of AF per month (p = 0.045) and larger pulmonary vein diameter (recessive model, p = 0.032).

Conclusions

Patients qualified for catheter ablation of AF have a significantly higher frequency of 4q25, 16q22 and 1q21 variants than the control group. The T allele of rs2200733 favours larger pulmonary veins and increased number of episodes of AF.     

复杂染色体重排的女性携带者与她健康的女儿

一例新生复杂染色体重排的女性携带者（complex chromosome rearrangement ,CCR）,易位涉及1号、5号和12号染色体。病人因2次自然流产而要求进行外周血淋巴细胞G显带核型分析。最初G显带核型疑为46,XX,t(1;5;12)(1pter→1q25::12q24→12qter;5qter→5p11::1q25→1qter;12pter→12q24::5p11→5pter).经荧光原位杂交（FISH）技术检测,证实患者的核型为46,XX,t(1;5;12)(1pter→1q23::12q22→12qter;5qter→5p11::1q25→1qter;12pter→12q22::1q23→1q25::5p11→5pter).7年后病人再次妊娠,并拒绝产前诊断。女婴足月分娩,生长发育正常。核型为46,XX。比较以前报告的女性复杂易位携带者与我们报告的病例可以认为,CCR并不总是表现为自然流产或分娩畸形儿,仍有机会生出正常的孩子。Abstract: We reported in the paper one case of a de novo complex chromosomal rearrangement (CCR) involving three different chromosomes,1, 5 and 12. Two pregnancies of the female carrier over three years resulted in two spontaneous abortions. Initial cytogenetic analysis of her peripheral lymphocyte by G banding suspected a karyotype 46,XX,t(1;5;12)(1pter →1q25::12q24→12qter;5qter→ 5p11::1q25→1qter;12pter →12q24::5p11→5pter). Fluorescense in -situ hybridization (FISH) was used to confirm the karyotype 46,XX,t(1;5;12)(1pter→1q23::12q22→12qter;5qter→5p11::1q25→1qter;12pter→12q22::1q23→1q25::5p11→5pter). Seven years later she was pregnant again and refused to have prenatal diagnosis. The fetus is normal both in phenotype and karyotype。Comparing previously reported female CCR carriers with the case, we conclude that female CCR carriers may not always present spontaneous abortion or have offspring with congenital malformation and can have chance to get a healthy child.     

Karyotype evolution in the bone marrow of a patient with Fanconi anemia: breakpoints in clonal anomalies of this disease

A 21-year-old Fanconi anemia patient developed refractory anemia. Laboratory studies revealed a transitory increased platelet count and a typical del(5q). Bone marrow karyotyping showed a -6, +der(6)t(1;6)(q12;p25) rearrangement and, two years later, a mosaic -6, +der(6),t(1:6)(q12;p25)/-2, +der 2), t(1;2)(q12;q37) constitution. The chromosome mechanism operating in this patient is discussed.     

Analysis of the DISC1 translocation partner (11q14.3) in genetic risk of schizophrenia

The Disrupted‐in‐Schizophrenia 1 (DISC1) locus on human chromosome 1 was identified as a consequence of its involvement in a balanced translocation (1;11)(q42.1;q14.3) segregating with major psychiatric disorders in a Scottish family. Recently a comprehensive meta‐analysis of genome‐wide association scan data found no evidence that common variants of DISC1 (1q42.1) are associated with schizophrenia. Our aim was to test for association of variants in the 11q14.3 translocation region with schizophrenia. The 11q14.3 region was examined by meta‐analysis of genome‐wide scan data made available by the Genetic Association Information Network (GAIN) and other investigators (non‐GAIN) through dbGap. P‐values were adjusted for multiple testing using the false discovery rate (FDR) approach. There were no single‐nucleotide polymorphisms (SNPs) significant (P < 0.05) after correction for multiple testing in the combined schizophrenia dataset. However, one SNP (rs2509382) was significantly associated in the male‐only analysis with P_FDR = 0.024. Whilst the relevance of the (1;11)(q42.1;q14.3) translocation to psychiatric disorders is currently specific to the Scottish family, genetic material in the chromosome 11 region may contain risk variants for psychiatric disorders in the wider population. The association found in this region does warrant follow‐up analysis in further sample sets .     

Characterization and chromosomal localization of five canine ATOX1 pseudogenes

We have isolated six ATOX1 loci from the canine genome in BAC clones. Sequence analysis showed that five of these clones correspond to processed pseudogenes. Fluorescent in situ hybridization allowed us to map the genuine ATOX1 gene to CFA4q24-->q31 and the ATOX1 pseudogenes to CFA19q13.1, CFA4q24-->q31, CFA18q24-->q25, CFA9q22.1 -->q22.2 and CFA20q11-->q12.     

De novo del(6)(q25) associated with macular degeneration

An eight-month-old girl with a de novo del(6)(q25) is described. She and other previous cases of 6q deletion showed concordance for developmental retardation associated with multiple unspecific congenital abnormalities, which do not yet allow the delineation of a syndrome. However, bilateral macular degeneration was found in the proposita and had been observed in another similar case, so it probably represents a distinctive feature of 6q terminal monosomy. This observation also suggests the existence of a dominant macular degeneration locus within 6q25----qter.     

Chromosomal Localization of the Human Genes for α1A, α1B, and α1E Voltage-Dependent Ca Channel Subunits

The α₁ subunit genes encoding voltage-dependent Ca²⁺ channels are members of a gene family. We have used human brain cDNA probes to localize the neuronal isoform genes CACNL1A4 (α_1A), CACNL1A5 (α_1B), and CACNL1A6 (α_1E) to 19p13, 9q34, and 1q25-q31, respectively, using fluorescence in situ hybridization on human chromosomes. These genes are particularly interesting gene candidates in the pathogenesis of neuronal disorders. Although genetic disorders have been linked to loci 9q34 and 19p13, no genetic disease related to Ca²⁺ signaling defects has yet been linked to these loci.     

Identification of the Locus Associated with Diabetic Nephropathy in Type 1 Diabetes Mellitus

Polymorphic tetranucleotide microsatellites D3S1512, D3S1744, D3S1550, and D3S2326 were used to study the association of chromosome region 3q21–q25 neighboring the angiotensin II receptor type 1 gene (AT ₂ R1) with diabetic nephropathy (DN) in diabetes mellitus type 1 (DM1). Allele and genotype frequencies were compared for DM1 patients with (N = 39) or without (N = 62) DN. Fisher's exact test with Bonferroni's correction revealed significant differences in frequencies of two D3S2326 alleles, one D3S1512 allele, and one allele and one genotype of D3S1550. No significant difference was observed with D3S1744. Thus, region 3q21–q25 proved tightly associated with DN in ethnic Russians with DM1 from Moscow.     

Mapping of a Gene for Long QT Syndrome to Chromosome 4q25-27

Long QT syndrome (LQTS) is a heterogeneous inherited disorder causing syncope and sudden death from ventricular arrhythmias. A first locus for this disorder was mapped to chromosome 11p15.5. However, locus heterogeneity has been demonstrated in several families, and two other loci have recently been located on chromosomes 7q35-36 and 3p21-24. We used linkage analysis to map the locus in a 65-member family in which LQTS was associated with more marked sinus bradycardia than usual, leading to sinus node dysfunction. Linkage to chromosome 11p15.5, 7q35-36, or 3p21-24 was excluded. Positive linkage was obtained for markers located on chromosome 4q25-27. A maximal LOD score of 7.05 was found for marker D4S402. The identification of a fourth locus for LQTS confirms its genetic heterogeneity. Locus 4q25-27 is associated with a peculiar phenotype within the LQTS entity.     

Genetic risk factors for nonsyndromic cleft lip with or without cleft palate in a Mesoamerican population: Evidence for IRF6 and variants at 8q24 and 10q25

INTRODUCTION: Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is one of the most common of all birth defects. NSCL/P has a multifactorial etiology that includes both genetic and environmental factors. The IRF6 gene and three further susceptibility loci at 8q24, 10q25, and 17q22, which were identified by a recent genome‐wide association scan (GWAS), are confirmed genetic risk factors for NSCL/P in patients of European descent. METHODS: A case‐control association study was performed to investigate whether these four risk loci contribute to NSCL/P in a Mesoamerican population using four single nucleotide polymorphisms to represent IRF6 and the three novel susceptibility loci. A total of 149 NSCL/P patients and 303 controls of Mayan origin were included. RESULTS: Single marker analysis revealed a significant association between NSCL/P and risk variants in IRF6 and the 8q24 and 10q25 loci. In contrast to previous findings, the association at the 8q24 locus was driven solely by homozygote carriers of the risk allele. This suggests that this locus might act in a recessive manner in the Mayan population. No evidence for association was found at the 17q22 locus. This may have been attributable to the limited power of the sample. CONCLUSION: These results suggest that IRF6 and the 10q25 and 8q24 loci confer a risk for the development of NSCL/P in persons of Mayan origin. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.     

Analysis of chromosomal aberrations involving chromosome 1q31-->q53 in a DMBA-induced rat fibrosarcoma cell line: amplification and overexpression of Jak2

In a study of DMBA-induced rat fibrosarcomas we repeatedly found deletions and/or amplifications in the long arm of rat chromosome 1 (RNO1). Comparative genome hybridization showed that there was amplification involving RNO1q31-->q53 in one of the DMBA-induced rat fibrosarcoma tumors (LB31) and a cell culture derived from it. To identify the amplified genes we physically mapped rat genes implicated in cancer and analyzed them for signs of amplification. The genes were selected based on their locations in comparative maps between rat and man. The rat proto-oncogenes Ccnd1, Fgf4, and Fgf3 (HSA11q13.3), were mapped to RNO1q43 by fluorescence in situ hybridization (FISH). The Ems1 gene was mapped by radiation hybrid (RH) mapping to the same rat chromosome region and shown to be situated centromeric to Ccnd1 and Fgf4. In addition, the proto-oncogenes Hras (HSA11p15.5) and Igf1r (HSA15q25-->q26) were mapped to RNO1q43 and RNO1q32 by FISH and Omp (HSA11q13.5) was assigned to RNO1q34. PCR probes for the above genes together with PCR probes for the previously mapped rat genes Bax (RNO1q31) and Jak2 (RNO1q51-->q53) were analyzed for signs of amplification by Southern blot hybridization. Low copy number increases of the Omp and Jak2 genes were detected in the LB31 cell culture. Dual color FISH analysis of tumor cells confirmed that chromosome regions containing Omp and Jak2 were amplified and were situated in long marker chromosomes showing an aberrant banding pattern. The configuration of the signals in the marker chromosomes suggested that they had arisen by a break-fusion-bridge (BFB) mechanism.     

Cloning and characterization of a novel human gene encoding a zinc finger protein with 25 fingers

This study reports cloning and characterization of a human cDNA encoding a novel human zinc finger protein, ZFD25. ZFD25 cDNA is 6118 bp long and has an open reading frame of 2352 bp that encodes a 783 amino acid protein with 25 C2H2-type zinc fingers. The ZFD25 cDNA also contains a region with high sequence similarity to the Krüppel-associated box A and B domain in the 5'-untranslated region, suggesting that ZFD25 belongs to the Krüppel-associated box zinc finger protein family. The ZFD25 gene was localized to chromosome 7q11.2. Northern blot analysis showed that ZFD25 was expressed in a wide range of human organs. In cultured endothelial cells, the mRNA level was decreased upon serum starvation.     

A case of macrocephaly-cutis marmorata telangiectatica congenita and review of neuroradiologic features

Macrocephaly-cutis marmorata telangiectatica congenita (M-CMTC) is characterized by macrocephaly, cutis marmorata, capillary malformations, toe syndactily, joint laxity and pre-natal overgrowth. Cerebral abnormalities might also be seen. We reported cerebral magnetic resonance imaging (MRI) findings of a case with M-CMTC, who had giant atrial septal aneurysm and atrial septal defect. Cerebral alterations determined by MRI were bilateral prominent lateral ventricles, bilateral cortical dysplasia, cavum septi pellucidum cyst and calvarial hemangioma. At 17th day of his life he suddenly developed cardiorespiratory arrest and died.     

Two cases of del(13q)-retinoblastoma and two cases of partial trisomy due to a familial insertion

A del(13)(q13q21.1) was found in a patient with bilateral retinoblastoma and mental retardation. The father was carrier of an ins(16;13)(q12.2;q13q21.1) which also was present in several other family members, and responsible for another case of del (13q)-retinoblastoma and two cases of trisomy for the inserted segment. This second del(13q) patient was also carrier of a balanced t(11;22).     

Site-specific recombination of the tal-1 gene is a common occurrence in human T cell leukemia.

The tal-1 gene is altered as a consequence of the t(1;14) (p32;q11) chromosome translocation observed in 3% of patients with T cell acute lymphoblastic leukemia (T-ALL). tal-1 encodes a helix-loop-helix (HLH) domain, a DNA binding and dimerization motif found in a number of proteins involved in cell growth and differentiation. We now report that an additional 25% of T-ALL patients bear tal-1 gene rearrangements that are not detected by karyotype analysis. These rearrangements result from a precise 90 kb deletion (designated tald) that arises independently in different patients by site-specific DNA recombination. Since the deletion junctions resemble the coding joints of assembled immunoglobulin genes, tald rearrangements are likely to be mediated by aberrant activity of the immunoglobulin recombinase. Moreover, t(1;14)(p32;q11) translocations and tald rearrangements disrupt the coding potential of tal-1 in an equivalent manner, and thereby generate a common genetic lesion shared by a significant proportion of T-ALL patients.     

Co-localization of susceptibility loci for psoriasis (PSORS4) and atopic dermatitis (ATOD2) on human chromosome 1q21

Psoriasis (PS) is a chronic inflammatory skin disorder characterized by keratinocyte hyperproliferation and altered differentiation. Atopic dermatitis (ATOD) is a chronic inflammatory, pruritic and eczematous disease frequently associated with respiratory atopy. These diseases are associated with distinct immunologic abnormalities and represent typical examples of complex diseases triggered by both genetic and environmental factors, as demonstrated by independent twin studies. Genome wide linkage studies have mapped susceptibility loci on several chromosomes (PSORS1-9; ATOD1-5). Four of them overlap on chromosomes 1q21, 3q21, 17q25 and 20p although ATOD is quite distinct from PS and these two diseases rarely occur together in the same patient. An association fine-mapping study has been performed to refine PSORS4 and ATOD2 susceptibility loci on chromosome 1q21 analyzing two independently collected cohorts of 128 PS and 120 ATOD trios. Genotype and haplotype analysis of PSORS4 and ATOD2 led us to detect significant p value for haplotypes defined by MIDDLE and ENDAL16 markers in both PS (p = 0.0000036) and ATOD (p = 0.0276), suggesting a strict co-localization within an interval of 42 kb. This genomic interval contains a single gene, LOR, encoding for loricrin. Polymorphic markers mapping in regulatory and coding regions did not show evidence of association in neither of the two diseases. However, expression profiles of LOR in skin biopsies have shown reduced levels in PS and increased levels in ATOD, suggesting the existence of a specific misregulation in LOR mRNA production.