Familial hypercholesterolaemia (FH) is an autosomal dominant disorder of lipoprotein metabolism. In the majority of patients FH is caused by mutations in the gene for the low-density lipoprotein receptor (LDLR), and to date more than 700 mutations have been reported worldwide. In this study, 36 paediatric patients with a clinical diagnosis of FH (20 homozygous and 16 heterozygotes) were screened for mutations in the LDLR gene. Each exon, with intron-exon junctions, was screened by capillary fluorescent SSCP (F-SSCP) and heteroduplex analysis. Samples showing different band patterns were sequenced. Ten novel (including three frame shift small deletions or insertions) and seven known mutations were detected. A total of 37 out of the predicted 56 FH-causing alleles were identified (66.1%). No patients with the R3500Q mutation in the APOB gene were found. W556R was the most common mutation, explaining 21.4% of the predicted defective LDLR alleles. The novel sequence changes were deemed to be pathogenic if they altered a conserved amino acid (L143P, D147E, Q233H-C234G, C347G) or occurred in or close to a splice site (IVS 16+5) and were absent in DNA from 50 healthy Turkish subjects. These data confirm the genetic heterogeneity of FH in Turkey, and demonstrate the usefulness of F-SSCP for mutation detection.

BACKGROUND:Endotoxin, with its potential to enhance type 1 immunity, is a significant player in the hygiene hypothesis. The combined effects of the genetic variants of various molecules in the endotoxin response pathway on asthma related phenotypes are largely unknown.OBJECTIVE:To investigate the effects of the genetic variants of CD14 and TLR4 genes on asthma phenotypes in a large number of asthmatic children.METHODS:613 asthmatic children were genotyped at the CD14-C159T, TLR4-A896G and TLR4-C1196T loci. IgE, eosinophil numbers and FEV1 were compared in 327 children who were not on any controller medications and were symptom free. Multivariate logistic regression was used to determine the factors associated with total IgE.RESULTS:Among children with atopic asthma, total IgE levels were significantly different among the three genotypes in the co-dominant model [CC: 435 kU/l (interquartile range: 146-820); CT: 361 (140-710); TT 204 (98-435), P = 0.035]. TT genotype was significantly and independently associated with lower IgE levels (OR: 0.5 95%; CI = 0.28-0.90, P = 0.021). Both TLR4-A896G and TLR4-C1196T polymorphisms were more frequent in the mild asthma group with atopy (P = 0.032, 0.018, respectively). The combined effects of the genetic variants in CD14 and TLR4 genes did not improve the observed associations.CONCLUSION:Our study demonstrates that the CD14-C159T promoter variant influences total IgE levels and also indicates that the T allele has a more profound effect on total IgE in children with atopic asthma. Polymorphisms in the TLR4 gene may be associated with milder forms of disease in atopic asthmatics in the population studied.

A boy presented at age 4 years with severe congenital hemolytic anemia characterized by highly elevated reticulocyte count (30-50%) and prominent basophilic stippling. Hb had been 4 g/dL at age 7 months. The patient was on a monthly transfusion regimen up to the age of 7 years, when he underwent splenectomy. After removal of the spleen, his Hb stabilized at 11 g/dL. No abnormal pattern was detected in hemoglobin electrophoresis at pH 9 and 6. In-vitro globin synthesis revealed the presence of an abnormal beta-chain in front of the gamma-chain. The beta(A)/beta(X) ratio was 0.77 at 30 min and 0.74 at 2 hr of incubation. Molecular analysis revealed that the patient had GCC-->GAC alteration at codon 27 (beta27(B9)Ala-->Asp) causing the abnormal hemoglobin Volga. The beta-cDNA derived from the beta-Hb Volga allele could be differentiated from HbA beta-cDNA on silver-stained gel. No imbalance in the mRNA of beta(A)/beta(Hb Volga) ratio was observed.

Selective intestinal malabsorption of vitamin B-12 causing juvenile megaloblastic anemia (MGA; MIM# 261100) is a recessively inherited disorder that is believed to be rare except for notable clusters of cases in Finland, Norway, and the Eastern Mediterranean region. The disease can be caused by mutations in either the cubilin (CUBN; MGA1; MIM# 602997) or the amnionless (AMN; MIM# 605799) gene. To explain the peculiar geographical distribution, we hypothesized that mutations in one of the genes would mainly be responsible for the disease in Scandinavia, and mutations in the other gene in the Mediterranean region. We studied 42 sibships and found all cases in Finland to be due to CUBN (three different mutations) and all cases in Norway to be due to AMN (two different mutations), while in Turkey, Israel, and Saudi Arabia, there were two different AMN mutations and three different CUBN mutations. Haplotype evidence excluded both CUBN and AMN conclusively in five families and tentatively in three families, suggesting the presence of at least one more gene locus that can cause MGA. We conclude that the Scandinavian cases are typical examples of enrichment by founder effects, while in the Mediterranean region high degrees of consanguinity expose rare mutations in both genes. We suggest that in both regions, physician awareness of this disease causes it to be more readily diagnosed than elsewhere; thus, it may well be more common worldwide than previously thought. (C) 2004 Wiley-Liss, Inc.

We report two novel mutations in factor XIIIA (FXIIIA) gene that caused congenital factor XIII deficiency in two unrelated patients. The first alteration, a missense mutation Leu235Arg in exon 6 of FXIIIA gene, is located in the putative calcium-binding part of the core domain of the enzyme. Replacement of non-polar hydrophobic leucine residue with positively charged arginine residue is likely to effect protein folding thus destabilizing the molecule. The second mutation is a 3-bp deletion in exon 14 of FXIIIA gene. This deletion is located in beta barrel 2 domain of the protein and results in translation of an aberrant FXIIIA molecule that lacks lysine residue either at positions 677 or 678. As this inframe deletion is located in a direct repetetive sequence of AAGAAG, that codes for two lysine residues, the exact location of deletion could not be detected.

The case of an 8-year-old male child with severe kernicterus sequelae is presented in this paper. The child's hemoglobin value varied between 6.0 and 10.8 g/dL and his reticulocyte count ranged between 3.4 and 46.0% during the steady-state condition and hyperhemolytic crisis, respectively. A chronic hemolytic typeof red cell G6PD deficiency was diagnosed. DNA studies indicate that the mutation was G6PD Guadalajara 1159 C M T (387 Arg M Cys) that is situated at the NADP binding site. Additionally, extra nucleotides of (TA) in the A(TA) n TAA motif of the promoter region of the uridine diphosphate-glucuronosyltransferase gene (UGT-1) were found to be homozygous in the patient. The coexistence of Gilbert syndrome with a chronic type of G6PD deficiency was suggested as a cause of neonatal hyperbilirubinemia leading to kernicterus.

Mutations in the melanocortin 4 receptor gene (MC4R) are the most common cause of monogenic human obesity. As part of our ongoing project entitled 'Turkish Obesity Genome Study' we determined the nucleotide sequence of the entire coding region of the MC4R gene in 40 morbidly obese subjects from independent families. Here we report a novel heterozygous mutation (N274S) in an adult female obese individual (age: 52 yrs, BMI 41.7 kg/m(2), height 158 cm, weight: 104 Kg). The sister of the index case (age: 55 yrs, height: 160 cm, weight: 110 Kg, BMI: 43 kg/m(2)) also carries the same mutation. Although both sisters were morbidly obese and hypertensive the index case had normal plasma insulin and fasting blood glucose levels whereas her sister had type 2 diabetes mellitus. No abnormalities of the reproductive function were present. Despite marked hyperphagia in childhood both sisters had a history of relatively diminished intensity of appetite after the age of 20. Of notice, index case was diagnosed to have cyclothymia whereas her sister was being treated for bipolar affective disorder. Detailed clinical evaluation revealed normal bone mineral density and serum calcium parameters as well as intact thyroid axis and hypothalamus-pituitary-adrenal axis in both patients. The human MC4-R deficient phenotype resembles the murine deficient state with regard to preserved reproductive function although hyperphagia, increased linear growth and absence of diabetes in mice are not observed in humans. Affected individuals have hyperphagia in childhood, which looses intensity later in life, and they also present with normal height and diabetes mellitus. Accumulating evidence indicate that melanocortin endocrine system or defective melanocortin signaling has inherently different characteristics in mice and humans resembling the variation observed with regard to leptin deficiency in both species.

A 30-year-old female who is homozygous for a Hb E-like abnormal hemoglobin and her immediate relatives were studied. Clinical examination of the proband revealed no abnormality. Routine hematological analysis showed that her hemoglobin level was 12 g/dL, MCV 82 fL, MCH 28 pg, RDW 15%. DNA sequence analysis indicated the presence of a G-->A substitution at codon 22 corresponding to an abnormal hemoglobin, namely Hb E-Saskatoon [beta22(B4)Glu-->Lys (GAA-->AAA)]. Absence of any abnormalities in clinical and routine hematological investigations of the homozygous patient indicated that the phenotypical expression of the Hb E-Saskatoon is very mild. Using a reverse transcription-polymerase chain reaction technique, the alpha/beta and betaX/betaA-mRNA (X = Hb E-Saskatoon) ratios were determined. Normal alpha/beta and betaX/betaA-mRNA ratios were found in the homozygous patient and in all heterozygotes, indicating that the respective mutation did not alter the stability of the mRNA. FokI restriction enzyme analysis of the polymerase chain reaction products obtained from the genomic DNA and/or beta-globin mRNA made it possible for rapid diagnosis of Hb E-Saskatoon, and for its differentiation from Hb E [beta26(B8)Glu-->Lys (GAG-->AAG)]. Analysis of the restriction fragment length polymorphism (RFLP) in the beta-globin gene complex of the index patient and of another unrelated family with a compound heterozygosity for Hb E-Saskatoon and beta-thalassemia revealed that the Hb E-Saskatoon mutation shared a common allele.

We provide the first description of a homozygote patient for the G→A substitution in the 5′ UTR of the β‐globin gene. The proband was a 17‐year‐old girl with β‐thalassaemia intermedia who had never received a blood transfusion. The physical examination revealed a well‐developed women with no facial or bony abnormalities. There was mild paleness and mild splenomegaly which was 2 cm below the costal margin. The haemoglobin (Hb) was 7·6 g/dl, Hb A2 5·4% and Hb F 14·6% of the total Hb. The Hb A2 of both parents was 3·5%. The Hb F level in the mother and father were 0·9, 1·2% and the mean cell volume (MCV) value was 70 and 72 fl respectively. DNA analysis of the β‐gene region of the propositus revealed homozygosity for a G→A substitution at nucleotide +22 relative to the β‐gene cap site, within a functional downstream region that was referred to as the DCE (downstream core element). In addition to the data obtained previously from in vitro transcription assays, clinical findings and in vivo expression studies gave some valuable clues about the effect of +22 G→A mutation on the expression of β‐gene. Phenotypic expression of this homozygous patient is highly suggestive that G→A substitution at nt +22 confers a relatively mild (silent) β+‐thalassaemia phenotype.

We report on two siblings with beta(+)-thalassemia intermedia. Molecular studies of the beta-globin gene indicated that the patients are homozygous for the -87 (C-->T) mutation. This genotype has not been previously described. Homozygosity for the -87 (C-->T) mutation produces a mild form of beta(+)-thalassemia associated with moderate Hb F elevation (26-38%) and highly elevated Hb A(2) (10-8.6%) levels, respectively. Hematological parameters of homozygous -87 (C-->G) and -87 (C-->A) mutations, and compound heterozygous patients with either C-->T, C-->G, or C-->A at -87 and one of the severe beta(+)- or beta(0)-thalassemia mutations, are given for comparison.

Four parents of three unrelated families who are obligatory beta-thalassemia heterozygotes and two parents with Hb Knossos are presented. In these subjects, although the red blood cell counts and red cell indices were compatible with beta-thalassemia trait, the Hb A2 values were between 1.9-2.9% of the total hemoglobin. Examination of the delta-globin gene by Southern blot, restriction endonuclease analysis, and by direct sequencing of amplified DNA revealed the presence of the (delta0) -7.2 kb Corfu type deletion, the (delta+) codon 27 (G-->T) and (delta0) IVS-I-2 (T-->C) mutations in trans or in cis with a severe beta-thalassemia allele, and the (delta0) codon 59 (-A) deletion in cis with the betaKnossos allele.

Molecular pathology of glucose-6-phosphate dehydrogenase (G6PD) was studied in 50 unrelated red cell G6PD deficient Turkish males. DNA analysis of G6PD genes revealed that 40 of the 50 subjects (80%) had G6PD B- 563T, 2 subjects (4%) A- (376G/202A) and one subject (2%) G6PD Chatam (1003A). The remaining 7 subjects (14%) did not have any of these three mutations.

The study presented here describes a Southern blot hybridization technique which is performed in a shorter time and safer than the classical one. In this study DNA was isolated from a small amount of blood sample and the probe for hybridization was prepared with 35S by polymerase chain reaction.

A 7.5 year old boy with myelodysplastic syndrome (MDS) of CMML type associated with trisomy 8 and elevated hemoglobin F (Hb F) value is presented. Hematological evaluation of the patient revealed that the Hb was 10 g/dl, MCV 110 FL, platelets 58 × 109/l, WBC 5.4 × 109/l with 24% atypical monocytes. Karyotype analysis revealed 47, XY, +8. Hb F value was 21% which was distributed heterogeneously among red cells. PCR amplified cDNA copies of circulating reticulocyte mRNA were used to measure the relative amounts of alpha-, β-, and gama - globin. There was marked increases in both alpha/β mRNA ratio (20%) and gama/(gama+β) mRNA ratio (35%) in the patient compared to normal subjects. The study indicated that increased transcription of a and g genes are partly responsible for the elevation of Hb F in MDS.

Griscelli disease (GD) is a rare disorder characterized by pigment dilution, immunodeficiency and occurrence of accelerated phase consisting of hemophagocytosis, pancytopenia and neurological manifestations. Allogeneic BMT in the early period is an important modality of treatment for GD. We carried out an alloBMT from an HLA-identical sibling donor on a 4-year-old girl who presented in accelerated phase with neurological manifestations including convulsions, strabismus, severe dysarthria, ataxia and clonus. She was treated with etoposide, methylprednisolone and intrathecal methotrexate for 8 weeks and underwent alloBMT after receiving a conditioning regimen including ATG (rabbit, 10 mg/kg × 5 days), Bu/Cy. 8 × 10 8 /kg nucleated bone marrow cells were given. Engraftment occurred early and the post-BMT period was uneventful. Currently, she is at 18 months post BMT with sustained engraftment and with a normal neurological examination except for minimal clonus. Long-term follow-up will determine the prognosis regarding the neurological findings.

The long-term biochemical and clinical effectiveness of allogenic bone marrow transplantation (BMT) was shown in a severely affected, transfusion-dependent 18-month-old female with congenital erythropoietic porphyria (CEP), an autosomal recessive inborn error of heme biosynthesis resulting from mutations in the uroporphyrinogen III synthase (URO-synthase) gene. Three years post-BMT, the recipient had normal hemoglobin, markedly reduced urinary porphyrin excretion, and no cutaneous lesions with unlimited exposure to sunlight. The patient was homoallelic for a novel URO-synthase missense mutation, G188R, that expressed less than 5% of mean normal activity in Escherichia coli, consistent with her transfusion dependency. Because the clinical severity of CEP is highly variable, ranging from nonimmune hydrops fetalis to milder, later onset forms with only cutaneous lesions, the importance of genotyping newly diagnosed infants to select severely affected patients for BMT is emphasized. In addition, the long-term effectiveness of BMT in this patient provides the rationale for future hematopoietic stem cell gene therapy in severely affected patients with CEP.

Selective complete C1q deficiencies (SCDC1q) of the complement component C1q are rare genetic disorders with high prevalence of lupus-erythematosus-like symptoms and recurrent infections. Among the 41 published cases from 23 families, 10 derive from 6 Turkish families. One particular mutation leading to a stop codon in the C1q A gene was first identified in members of a Gypsy family from the Slovac Republic. Later the same mutation has been found in all cases in four SCDC1q families from Turkey suggesting that one particular defective allele may be present in the populations of Southeastern Europe and Turkey.This study was undertaken to investigate the frequency of C-->T mutation in exon II of C1qA gene in Turkish population by using allele-specific polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP). Among the 1544 patients from 15 pediatric departments and an additional 89 SLE patients of various ages no C1qA gene mutation was found. There were 43 heterozygous and 4 homozygous mutations in 161 family members or relatives investigated from the 4 families known with SCDC1q. Among the 223 inhabitants who were nonrelative to the 3 SCDC1q families living in the same village were screened for mutation and one heterozygous individual was observed.Although this mutant allele appears to be at a low prevalence in the population rested, individuals with recurrent infections or symptoms of lupus erythematosus-like syndrome should be tested for this mutation to rule out this type of C1q deficiency.