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Resting cerebral glucose metabolism was assessed by 18[F]-fluorodeoxyglucose in 11 Down syndrome patients. Standardized uptake values were determined on a pixel-by-pixel basis from the measured tissue-activity data. The results revealed a mean overall 18[F]-fluorodeoxyglucose uptake in the Down syndrome patients close to that observed in the control group, consisting of children and young adults. However, the standard deviation of the standardized uptake values was much higher in the Down syndrome group in almost all voxels relating to the gray matter. The statistical parametric mapping method was applied to compare the cerebral 18[F]-fluorodeoxyglucose accumulation patterns of the Down syndrome and control groups. Six regions (clusters) were found for which the glucose uptake was higher in the Down syndrome patients than in the control group. The anatomic localization of these clusters was based on magnetic resonance investigations and a brain-atlas technique. The localization of the identified clusters with an increased glucose metabolism in the Down syndrome patients suggests that these subjects have an enhanced resting neuronal activity in cortical areas involved in reasoning, cognition, and speech as compared with normal subjects. [Copyright &y& Elsevier]

Male carriers with balanced reciprocal translocations can produce a variable proportion of unbalanced gametes resulting in reproductive failures. The presence of a structural rearrangement may induce an interchromosomal effect. This is characterized by abnormal bivalents not involved in the reorganization thereby yielding non-disjunction, which would present as aneuploid spermatozoa for these chromosomes. In the present case report segregation analysis of the sperm and investigation of interchromosomal effect were carried out using cytogenetic and fluorescence in situ hybridization (FISH) analysis on blood lymphocytes. The karyotype of the patient was 46,XY,t(3;6)(q21;q23). During sperm segregation analysis a total of 2,002 sperms were evaluated, of which 46.8% showed normal/balanced (alternate segregation mode) and 53.2% of sperm showed an abnormal signal pattern. A significant difference in the frequency of the estimated number of chromosome anomalies was observed in the translocation carrier when compared to the normozoospermic group ( P < 0.0001) and the oligozoospermic group ( P < 0.0001). Meiotic segregation analysis of sperm together with aneuploidy assessment for X, Y, and 17 chromosomes using FISH allows for the determination of a reproductive prognosis in male balanced translocation carriers and can be used for appropriate genetic counseling. [ABSTRACT FROM AUTHOR]

Infertile men with low sperm concentration and/or less motile spermatozoa have an increased risk of producing aneuploid spermatozoa. Selecting spermatozoa by hyaluronic acid (HA) binding may reduce genetic risks such as chromosomal rearrangements and numerical aberrations. Fluorescence in-situ hybridization (FISH) has been used to evaluate the presence of aneuploidies. This study examined spermatozoa of 10 oligozoospermic, 9 asthenozoospermic, 9 oligoasthenozoospermic and 17 normozoospermic men by HA binding and FISH. Mean percentage of HA-bound spermatozoa in the normozoospermic group was 81%, which was significantly higher than in the oligozoospermic (P < 0.001), asthenozoospermic (P < 0.001) and oligoasthenozoospermic (P < 0.001) groups. Disomy of sex chromosomes (P = 0.014) and chromosome 17 (P = 0.0019), diploidy (P = 0.03) and estimated numerical chromosome aberrations (P = 0.004) were significantly higher in the oligoasthenozoospermic group compared with the other groups. There were statistically significant relationships (P < 0.001) between sperm concentration and HA binding (r = 0.658), between sperm concentration and estimated numerical chromosome aberrations (r = -0.668) and between HA binding and estimated numerical chromosome aberrations ( r= -0.682). HA binding and aneuploidy studies of spermatozoa in individual cases allow prediction of reproductive prognosis and provision of appropriate genetic counselling. [ABSTRACT FROM AUTHOR]

The spectrum of lissencephaly ranges from absent (agyria) or decreased (pachygyria) convolutions to less severe malformation known as subcortical band heterotopia. Mutations involving LIS1 and TUBA1A result in the classic form of lissencephaly, whereas mutations of the DCX gene cause lissencephaly in males and subcortical band heterotopia in females. This report describes the clinical manifestations and imaging and genetic findings in 2 boys with lissencephaly and a girl with subcortical band heterotopia. An ovel mutation (c.83_84delAT, p.Tyr28Phefs*31) was identified in LIS1 in 1 of the boys with lissencephaly and another novel mutation (c.200delG, p.Ile68Leufs*87) was found in DCX in the girl with subcortical band heterotopia. The mutations appeared in the first half of the genes and are predicted to result in truncated proteins. A mutation was found in the TUBA1A gene (c.1205G>A, p.Arg402His) in the other boy. This mutation affects the folding of tubulin heterodimers, changing the interactions with proteins that bind microtubules. [ABSTRACT FROM AUTHOR]

Abstract: Solitary Median Maxillary Central Incisor Syndrome (SMMCI) is a rare malformation syndrome consisting of multiple, mainly midline defects. Some authors suggest that it is a mild manifestation of the wide spectrum of holoprosencephaly, others classify it rather as a distinct entity. Authors report a case of SMMCI presenting with growth retardation, mild intellectual disability and absence of puberty. Cytogenetic and molecular cytogenetic investigations could identify no abnormalities. The presence of a single maxillary incisor called for further investigations to clarify hidden anomalies, these were empty sella, panhypopituitarism, hypothyroidism, and hypoplasia of the inner genitals. Based on the above findings, growth hormone, estrogen, and L-thyroxine substitution was introduced, which resulted in satisfactory longitudinal growth and onset of sexual maturation. We suggest genetic counselling and if needed, invasive investigations in female patients with short stature and absent/delayed puberty, with or without sex chromosomal anomalies, as the adequate therapy and even the quality of life of patient depends largely on the knowledge of their anatomical and endocrine status. [Copyright &y& Elsevier]

The Smith–Lemli–Opitz (SLO) syndrome is a multiple congenital anomaly with mental retardation due to a decreased or lack of activity of 7-dehydrocholesterol reductase as a consequence of mutations of the DHCR7 gene. This paper describes a special patient with SLO syndrome. Laboratory examination showed low cholesterol (2.77 mmol/L) and increased 7-dehydrocholesterol level (102 mg/L). Molecular genetic analysis revealed a compound heterozygosity c.964-1G>C/p.G366V (c.G1370T) of the proband. The p.G366V is a novel mutation of the DHCR7 gene with guanine by thymine nucleotide exchange resulting in glycin by valin amino acid exchange in the dehydrocholesterol reductase enzyme. Simvastatin (0.2 mg/kg/day) and cholesterol replacement therapy (150–250 mg/kg/day) led to significant improvement in the patient's laboratory findings (7-dehydrocholesterol, cholesterol) as well as in his behavior and gross motor function. Our patient demonstrates that the c.964-1G>C/p.G366V (c.G1370T) genotype of combined heterozygosity is associated with a typical form of SLO syndrome along with moderately altered laboratory findings and a favorable biochemical response to cholesterol and simvastatin treatment. [ABSTRACT FROM AUTHOR]