A novel missense mutation in the NSDHL gene identified in a Lithuanian family by targeted next-generation sequencing causes CK syndrome.

The NSDHL gene encodes 3β-hydroxysteroid dehydrogenase involved in one of the later steps of the cholesterol biosynthetic pathway. Mutations in this gene can cause CHILD syndrome (OMIM 308050) and CK syndrome (OMIM 300831). CHILD syndrome is an X-linked dominant, male lethal disorder caused by mutations in the NSDHL gene that result in the loss of the function of the NSDHL protein.

R368X mutation in MID1 among recurrent mutations in patients with X-linked Opitz G/BBB syndrome.

Opitz G/BBB syndrome is a genetically heterogeneous condition, with both autosomal dominant and X-linked forms. The MID1 gene is associated with X-linked Opitz G/BBB syndrome. Most mutations identified are unique, which makes it difficult to assess possible genotype/phenotype correlations.

Considering specific clinical features as evidence of pathogenic copy number variants.

Since the introduction of high-resolution microarray technologies, it has become apparent that structural chromosomal rearrangements can lead to a wide variety of clinical manifestations, including developmental delay/intellectual disability (DD/ID). It has been shown previously that the diagnostic yield of genome-wide array-based identification of submicroscopic alterations in patients with ID varies widely and depends on the patient selection criteria. More attempts have recently been made to define the phenotypic clues of pathogenic copy number variants (CNVs).

Relevance of nasal potential difference in diagnosis of cystic fibrosis among children.

OBJECTIVE. The aim of this study was to estimate the significance of nasal potential difference (NPD) in the diagnosis of cystic fibrosis (CF) in children with clinical symptoms suggestive of the disease, positive sweat test results, and/or genetically confirmed diagnosis. MATERIAL AND METHODS.

A new single gene deletion on 2q34: ERBB4 is associated with intellectual disability.

We report on a 15-year-old patient with hyperactivity, intellectual disability and severe speech developmental delay. An array CGH analysis revealed de novo 2q34 deletion, 958 kb in size, involving a single protein coding gene ERBB4 (position 212,505,294-213,463,152; NCBI build 36). The ERBB4 gene is important in numerous neurobiological processes in both the developing and the adult brain.

Familial distal monosomy 5p15.3-pter with trisomy 12q24.2-qter resulting in neurodevelopmental delay and dysmorphic features.

Developmental delay and brain anomalies leading to significant morbidity and mortality are frequently caused by chromosomal rearrangements. We report on a familial unbalanced translocation resulting in distal monosomy 5p15.3-pter with trisomy 12q24.

Clinical and molecular characterization of a second case of 7p22.1 microduplication.

The use of high-resolution microarray technology for investigation of patients with intellectual disability and/or congenital anomalies provided the unique possibility to identify new microdeletion/microduplication syndromes and discover the dosage sensitive genes, which are implicated in the manifestation of various genetic conditions. Microduplication of the 7p22.1 region, 1.

A single gene deletion on 4q28.3: PCDH18--a new candidate gene for intellectual disability?

We report a boy with severe developmental delay, seizures, microcephaly, hypoplastic corpus callosum, internal hydrocephalus and dysmorphic features (narrow forehead, round face, deep-set eyes, blue sclerae, large and prominent ears, nose with anteverted nares, thin upper lip, small and wide-spaced teeth, hyperextensibility of the elbows, wrists, and fingers, fingertip pads, broad hallux, sacral dimple), carrying a 1.53 Mb interstitial deletion at 4q28.3.

De novo 5q35.5 duplication with clinical presentation of Sotos syndrome.

We report on a girl with developmental delay and a de novo 264 kb interstitial duplication in the region of Sotos syndrome at 5q35.3 in the immediate vicinity of critical NSD1 gene, but manifesting the phenotype, of overgrowth both prenatal stage and postnatal, macrocephaly, developmental delay, and resembling that of Sotos syndrome, rather than the recently reported syndrome of reciprocal duplication. The duplication is located right downstream from the NSD1 gene, a region which appears critical for the expression of the gene as regulatory elements might be disrupted or the expression of a not amplified critical gene might be otherwise affected by the duplicated region.

Genetic structure of Europeans: a view from the North-East.

Using principal component (PC) analysis, we studied the genetic constitution of 3,112 individuals from Europe as portrayed by more than 270,000 single nucleotide polymorphisms (SNPs) genotyped with the Illumina Infinium platform. In cohorts where the sample size was >100, one hundred randomly chosen samples were used for analysis to minimize the sample size effect, resulting in a total of 1,564 samples. This analysis revealed that the genetic structure of the European population correlates closely with geography.

Validation of PAH genotype-based predictions of metabolic phenylalanine hydroxylase deficiency phenotype: investigation of PKU/MHP patients from Lithuania.

Background: Phenylalanine hydroxylase (PheOH) deficiency is inherited as an autosomal recessive trait. The associated hyperphenylalaninemia phenotype is highly variable, primarily due to great allelic heterogeneity in the PAH locus. The goal of our study was to assess the relationship between individual PAH locus mutations and biochemical and metabolic phenotypes in phenylketonuria (PKU) and mild hyperphenylalaninemia (MHP) patients.