Quantitative trait loci associated with androgenic responsiveness in triticale (×Triticosecale Wittm.) anther culture.

Quantitative trait loci (QTLs) associated with androgenic responsiveness in triticale were analyzed using a population of 90 DH lines derived from the F1 cross between inbred line 'Saka 3006' and cv. 'Modus', which was used in a number of earlier studies on molecular mapping in this crop. Using Windows QTL Cartographer and MapQTL 5.0, composite interval mapping (CIM) and association studies (Kruskal-Wallis test; K-W) for five androgenesis parameters (androgenic embryo induction, total regeneration and green plant regeneration ability, and two characteristics describing final androgenesis efficiency) were conducted. For the studied components of androgenic response, CIM detected in total 28 QTLs which were localized on 5 chromosomes from A and R genomes. Effects of all QTLs that were identified at 2.0 or above of the LOD score explained 5.1-21.7 % of the phenotypic variation. Androgenesis induction was associated with seven QTLs (LOD between 2.0 and 5.8) detected on chromosomes 5A, 4R, 5R and 7R, all of them confirmed by K-W test as regions containing the markers significantly linked to the studied trait. What is more, K-W test revealed additional markers on chromosomes: 5A, 2BL, 7B and 5R. Both total and green regeneration ability were controlled by genes localized on chromosome 4A. Some of the QTLs that affected final androgenesis efficiency were identical with those associated with androgenic embryo induction efficiency, suggesting that the observed correlation may be either due to tight linkage or to pleiotropy. Key message Five regions of the triticale genome were indicated as revealing significant marker/trait association. Markers located in these regions are potentially useful for triticale breeding through marker-assisted selection.

The occurrence and the type of germline mutations in the RET gene in patients with medullary thyroid carcinoma and their unaffected kindred's from Central Poland.

We aimed to investigate the occurrence and types of pathogenic mutations in the RET gene in patients with MTC of the Central Poland population and in their relatives. DNA was extracted from the peripheral blood lymphocytes of a total of 330 persons, including 235 MTC patients and 95 of their unaffected kindred's. Exons 10, 11, 13, 14, 15 and 16 of the RET gene were amplified by PCR and sequenced. Sixty-seven people were found to carry pathogenic, germline mutations in the RET gene. In exon 10, C609F, C609R and C609Y (3 families), C618G, C618F (2 families), and C620G (4 families) mutations were identified. In exon 11, C634R (8 families) and C649L mutations (1 patient) were found. Five families carried Y791F mutation in exon 13. One patient with PTC revealed the presence of a Y791F mutation. In 3 families, exon 14 of the RET gene harbored the following mutations: V804L (1 patient), E819K (1 patient) and R844Q (1 patient). In 1 family, the S891A mutation was identified in exon 15, 3 families were found to carry mutations in exon16, R912P in 1 family and M918T in 2 families. In summary, of the 235 patients affected by MTC, 46 (19.6%) carried pathogenic RET gene mutations, 1 patient with RET mutation had kidney carcinoma, and 1 had PTC. The results show the occurrence of a variety of mutations prevalent in patients with MTC in the population of Central Poland. These results may contribute to a better diagnosis of medullary thyroid carcinoma.

Primary vascular thrombosis after renal transplantation in children.

The aim of the study was to assess the incidence, causes, diagnostic and treatment modalities, and outcome of vascular thrombosis after kidney transplantation in children. Between 1984 and 1995 we performed 176 kidney transplants in pediatric recipients aged 1 to 18 years. Vascular thrombosis followed 7 transplants, 4 were renal vein and 3 arterial thromboses. Venous thromboses occurred 2 to 12 days after transplantation. All of the patients with a renal vein thrombosis lost their grafts. Arterial thrombosis developed in 2 cases of double renal arteries which were separately anastomosed into the recipient vessels. One graft was lost, but the other was saved by thrombolytic therapy (streptokinase). One child experienced intrarenal segmental artery thrombosis during acute vascular rejection, which resolved following combined anti-rejection and thrombolytic (intra-arterial streptokinase) treatment with full recovery of graft function. In all, vascular thrombosis complicated 7 out of 176 transplants (4.0%), and was the cause of 5 graft losses (2.8%). The incidence of vascular thrombosis was not increased in grafts with vascular anomalies (3/34 v. 4/142; p>0.05, chi sq.). We conclude that acute tubular necrosis, rejection and unstable volemia may predispose to vascular thrombosis. In selected cases, early diagnosis of vascular thrombosis may enable graft salvage by surgical or thrombolytic treatment.

Diagnosis and monitoring of cytomegalovirus infection after liver transplantation in children.

Cytomegalovirus infection (CMV) complicated the posttransplant course in 9 of 24 children after liver transplantation. We found specific antibodies (IgG and IgM) to be of very low value in diagnosis and monitoring of CMV infection after liver transplantation. Detection of CMV-DNA by PCR method in the blood or urine was very useful for diagnosis, but less for monitoring of the course of disease and its treatment. Measurements of early immediate CMV antigen (IEA), in peripheral blood leucocytes allowed for very early diagnosis of CMV infection and correlated well with the course of disease and response to treatment of the patient.