Linkage confirms canine pkd1 orthologue as a candidate for bull terrier polycystic kidney disease.

Bull terrier polycystic kidney disease (BTPKD) is a Mendelian disorder with many features reminiscent of human autosomal dominant polycystic disease, the latter disease being due to mutations at PKD1 and PKD2 loci. We investigated the role of the canine pkd1 orthologue in BTPKD via linkage analysis of a large kindred in which the disorder is segregating. Twelve microsatellite markers around the canine pkd1 locus (CFA6) were amplified from the genomic DNA of 20 affected and 16 unaffected bull terriers. An additional 28 affected dogs were genotyped at five key microsatellites. A highly significant multi-point LOD score that peaked over the canine pkd1 locus was observed (LOD = 6.59, best two-point LOD score LOD = 6.02), implicating this as the BTPKD locus.

Nucleic acid amplification technique for detection of Chlamydia trachomatis infection from clinical urogenital swabs.

An improved nucleic acid amplification test (NAAT) to detect Chlamydia trachomatis infections, based on PCR amplification within its cryptic plasmid (CT1/CT2 Test) was developed. DNA was extracted from urogenital swabs and a 594-bp long DNA fragment from the cryptic plasmid (pCT) was amplified. The sensitivity and specificity of the CT1/CT2 Test were determined to be 100 and 99%, respectively, when directly compared with current amplification kit for sexually transmitted diseases (MPCR). Basic epidemiological data related to the patients attending gynecological and/or urological clinics are also provided. The overall prevalence rate in this group of patients suspected for C. trachomatis infection was determined to be about 95 per 1000 (88 and 107 per 1000 in females and males, respectively). It demonstrates that the CT1/CT2 Test is suitable for epidemiological screening and/or diagnostic practice.

Molecular detection of Ureaplasma urealyticum infection from clinical urogenital swabs.

A simple nucleic acid amplification test (NAAT) was developed for detection of Ureaplasma urealyticum infection based on the PCR amplification of the urease gene (UU1/UU2 Test). DNA was extracted from urogenital swabs and a 225-bp long DNA fragment was amplified by PCR. NAAT was compared to the commercial amplification kit for sexually transmitted disease reference assay. The sensitivity and specificity of the UU1/UU2 Test were determined to be 100 and 98.9%, respectively. The overall prevalence rate in this group of patients was found to be about 236 per 1000 (283 and 166 per 1000 in females and males, respectively). These data demonstrate that UU1/UU2 Test is suitable for effective epidemiological screening and/or diagnostic practice.

The second generation of the International Equine Gene Mapping Workshop half-sibling linkage map.

A low-density, male-based linkage map was constructed as one of the objectives of the International Equine Gene Mapping Workshop. Here we report the second generation map based on testing 503 half-sibling offspring from 13 sire families for 344 informative markers using the CRIMAP program. The multipoint linkage analysis localized 310 markers (90%) with 257 markers being linearly ordered. The map included 34 linkage groups representing all 31 autosomes and spanning 2262 cM with an average interval between loci of 10.1 cM. This map is a milestone in that it is the first map with linkage groups assigned to each of the 31 automosomes and a single linkage group to all but three chromosomes.

Polymorphism of the p53 gene within the codon 72 in lung cancer patients.

We tested the codon 72 single nucleotide polymorphism (SNP) of the tumor suppressor gene p53 for association with lung cancer. In our hospital-based case-control study, 168 lung cancer patients (134 males and 34 females) and 148 controls without malignant diseases were recruited. The genotype characteristics were determined by PCR-based RFLP method using DNA extracted from peripheral blood. Only in lung cancer patients but not in the controls we found both significant decrease of A1 allele of the p53 codon 72 (p=0.024, OR 0.56, 95% CI 0.43-0.72) and A1/A1 homozygous genotype (p=0.006, OR 0.27,95% CI 0.15-0.51). The results of this study suggest a protective effect of A1 allele against lung cancer.

Frequency of spinocerebellar ataxia types 1, 2, 3, 6, and 7 in Australian patients with spinocerebellar ataxia.

The frequencies of various genetically defined spinocerebellar ataxias (SCAs) vary in different populations presumably due to founder effects. No data have been published on the Australian population. Although predominantly of Anglo-Celtic extraction, Australia has also received considerable influx from southeastern Europe and more recently eastern and southeastern Asia. We examined the frequency of mutations for SCA types 1, 2, 3, 6, and 7 in southeastern Australia. Of 88 pedigrees with multiple-affected members, SCA type 1 (SCA1) accounted for 16%, SCA2 for 6%, SCA3 for 12%, SCA6 for 17%, SCA7 for 2%, and 47% (41 pedigrees) were negative for each of SCA1, 2, 3, and 6. Twenty of the 41 negative pedigrees were also negative for dentatorubralpallidoluysian atrophy, and indeed dentatorubralpallidoluysian atrophy has not been reported in Australia. In addition, no pedigree information was available on a further four patients with SCA1, three patients with SCA2, three patients with SCA3, and three patients with SCA6. One SCA1 and two SCA2 patients had no other known affected family members. In total, of 63 pedigrees or individuals with positive tests, 30% were those with SCA1, 15% with SCA2, 22% with SCA3, 30% with SCA6, and 3% with SCA7. Judging by pedigree names, four of the nine SCA2 positive individuals/pedigrees were of Italian extraction, and four of the 14 SCA3 positive individuals/pedigrees were of Chinese descent, whereas only 1 of the 20 SCA1 positive individuals/pedigrees were non-Anglo-Celtic. These results are in accordance with the known ethnic composition of the Australian population and with gene frequencies in these constituent ethnic groups reported by others. The frequency of large-normal alleles for SCA1 and SCA3 in the population reflects the prevalence of these two diseases, supporting the hypothesis that disease alleles arise by expansion of large-normal alleles.

Two cases of prenatal analysis for the pathogenic T to G substitution at nucleotide 8993 in mitochondrial DNA.

We report the outcome of two prenatal analyses for the T to G mutation at nucleotide 8993 in the mitochondrial DNA. This mutation is associated with neurogenic muscle weakness, ataxia and retinitis pigmentosa (NARP) and the neurodegenerative condition, Leigh syndrome. One prospective mother was the sister of a severely affected individual, and had previously had an unaffected child and a stillborn child. The second prospective mother had two unaffected children and two affected children. The mutation was not detected in the chorionic villus sample from one fetus nor in the amniocytes from the other fetus. Both pregnancies were continued, and the resulting children were healthy at two years and five years of age. Prenatal diagnosis of this mitochondrial DNA mutation is an option likely to be acceptable to some families to prevent the birth of a child at high risk for neurological disease.

Spinal muscular atrophy: untangling the knot?

Spinal muscular atrophy (SMA), a clinically and genetically heterogeneous group of neuromuscular diseases, is a disorder of motor neurones characterised by degeneration of spinal cord anterior horn cells and muscular atrophy. SMA is an autosomal recessive disorder with a carrier frequency of about 1150. Three candidate genes, the survival motor neurone (SMN) gene, the neuronal inhibitory protein (NAIP) gene, and the p44 (subunit of basal transcription factor TFIIH) gene, have been considered as genes involved in this condition. The region spanning these genes has a complex organisation including duplications, repetitive sequences, truncated genes, and pseudogenes, which makes molecular analysis of this condition difficult. Although deletions have been found in the majority of SMA patients, a few microrearrangements (like duplications, missense mutations, microdeletions, and gene conversions) localised in the telomeric form of the SMN gene have also been reported. The function of the protein encoded by the SMN gene is still not fully understood but recent studies have indicated that it is found intracellularly in gems, novel nuclear structures. Its interaction with other proteins suggests a role in mRNA processing and metabolism. Whether the NAIP gene protein and other apoptosis associated proteins are directly involved in the initial stages of neurone degeneration and apoptosis, or acting downstream on the pathological pathway, has been difficult to determine. Further studies will be required to elucidate possible functional interactions between these proteins.

Duplex PCR for Autosomal Dominant Spinocerebellar Ataxia Testing: A Nonradioactive Rapid Screening Method.

Background: Current DNA diagnostic testing for spinocerebellar ataxias (SCAs) 1, 2, 3, and 6 involves four separate tests based on radioactively-labeled poly merase chain reaction (PCR). Although this approach allows accurate allele sizing, it also is time-consuming and requires manipulation with hazardous radioactive isotopes. Methods and Results: A rapid screening approach was developed based on a nonradioactive and duplexed PCR assay coupling SCA 1 and SCA 3 together and SCA 2 and SCA 6 together. This was achieved by designing new primers that amplify all normal and mutant alleles in nonoverlapping size ranges. A series of negative and positive samples previously tested with the single radioactively labeled PCRs was tested using the new duplex PCRs; 100% concordancy was achieved. Conclusion: This novel approach of nonradioactive, duplex PCRs for autosomal dominant spinocerebellar ataxias is a rapid, reliable, and cost-effective diagnostic screening approach that is suitable for laboratories with high sample load and/or laboratories seeking to reduce their use of radioisotopes.

Spinal Muscular Atrophies: An Ongoing Diagnostic Dilemma?

Background: Spinal muscular atrophies (SMAs) are a group of autosomal recessive disorders of anterior horn cell degeneration. Three genes-survival motor neuron (SMN), neuronal apoptosis inhibitory protein (NAIP), and, more recently, p44 (subunit of basal transcription factor II)-have been considered as candidate genes. The region spanning these genes has a complex organization, which makes molecular analysis difficult. Methods and Results: Molecular genetic testing of deletions of exons 7 and 8 of the SMN(T) (telomeric copy) gene and exon 5 of the NAIP(T) (telomeric copy) gene was performed in 39 diagnosed SMA patients, 31 cases referred as possible SMA, and 24 cases of prenatal diagnosis of SMA. Linkage analysis using markers flanking the SMA region was also performed. In general, the findings of involvement of SMN and NAIP gene deletions in patients diagnosed with SMA are in agreement with those previously published. One possible SMA case was found to be homozygously deleted only for exon 7 of SMN(T) and one deleted only for exon 5 of the NAIP(T) gene. Conclusions: SMAs exemplify human inherited disorders in which application of a variety of different techniques and a search for mutations in multiple genes are involved. Deletion testing of candidate genes (SMN, NAIP) is a powerful approach in patients affected or suspected of being affected with SMA. It is proposed that the direct SMN gene deletion test can be offered as the only test for prenatal diagnosis of SMA in families in which the clinically affected sibling has also been shown to have the homozygous deletion.

Some genetic markers in Valachian (Olachian) Gypsies in Slovakia.

ABO, RH, MN, Kell, P, Lutheran, Lewis, HP, GC, ACP, PGM1, ADA and ESD markers were studied in 122 Valachian Gypsies from Vinodol in West Slovakia. The Valachian Gypsies represent about 5% of the total number of Gypsies (400,000) living in the Czech and Slovak Republic. The results show that their gene pool differs greatly from the one obtained for other Gypsy populations. Since Valachian Gypsies form an endogamous isolate with a high degree of inbreeding, genetic drift and founder effect might have contributed to this difference.

[Analysis of the effect of 2 criteria in the creation of age groups on the value spread of selected somatic parameters]. / Analýza vplyvu dvoch kritérií tvorby vekových skupín na rozptyly hodnôt vybraných somatických parametrov.

In the paper we present the results from the statistic analysis of the effect of two age-group creation criterions (1-st criterion--f.e. the 7 years old--from 6,500 to 7,499 years, 2-nd criterion--f.e. the 7 years old--from 7,000 to 7,999) on value dispersion of somatic characteristics chosen. We analyzed the body weight and body height in the set consists of 846 Gypsy children from 7 to 13 years of age. The dispersions of individual values of parameters followed for both criterions were tested by F-test, average values by un-pair Student's t-test. We found that the both criterions have no effect on value dispersion of evaluated somatic characteristics, except of two cases. Further, average values of testing parameters by criterion No. 1 are somewhat lower in comparison with those by criterion No. 2. Statistically significant differences are however incidental and rare. We suggest that in the case of population studies concerning with body growth and development it is possible to compare the sets with different age-group creation criterions.

[Bone age of preschool children in Eastern Slovakia]. / Kostný vek predskolských detí z východného Slovenska.

The authors present the results of evaluation of the skeletal maturation in 579 children aged 1-5 years. Bone maturation was evaluated, based on skeletal age, by the Tanner-Whitehouse II method (Tanner et al., 1975). It was found that girls up to the age of three years had lower and in the more advanced age groups higher values of skeletal age than boys. Boys were retarded as regards skeletal age in relation to chronological age on average by 0.28 years and girls by 0.25 years.

[Comparison of physical growth in school-children living in children's residential facilities and in families with emphasis on the gypsy ethnic group]. / Porovnanie telesného rastu skolských detí z detských domovov a rodín so zameraním na rómske etnikum.

The authors investigated the growth of 1208 gipsy and non-gipsy children living with their families and in childrens homes. They revealed that gipsy children from childrens homes were shorter, lighter and had a smaller chest circumference as compared with gipsy children living with their families. This applied only to younger school children. Somatic development caught up in boys at the age of 11-12 years and in girls approximately 1-2 years sooner. The values of the body mass index in boys declined with age. In girls this decline was found only up to the age of 11 to 12 years. Non-gipsy children from childrens homes were smaller than non-gipsy children according to Slovak standards (Lipková et al.; 5); this was particularly marked in boys. The authors found also that the somatic development of gipsy children from childrens homes oscillates between the somatic development of non-gipsy children according to the Slovak standards and the somatic development of gipsy children from families but only during later school age.

[Bone age of preschool-age children in the Eastern Slovakia Region]. / Kostný vek predskolských detí z Východoslovenského kraja.

In a group of 579 children the bone age was assessed by the Tanner-White house II method. It was revealed that girls up to the age of three years have lower values of bone age than boys who are ahead in subsequent age groups. Boys lagged behind as regards bone age in relation to chronological age by 0.4 years and girls by 0.3 years.

[Body growth in low birth weight premature children up to 5 years of age]. / Telesný rast nedonosených detí s nízkou pôrodnou hmotnost'ou do 5 rokov.

Investigation of the growth in 488 premature infants born with a low birth weight, compared with infants born in term with a birth weight above 2,500 g at the age of 1-5 years. Body weight, height, head circumference and chest circumference were assessed as well as Quetelet-Kaup-Gould and Quetelet-Bouchard index. It was found that premature infants are retarded in the above parameters, as compared with mature infants, still at the life of live years.