Sindrome di Turner in mosaico in madre e figlia con anomalie del cariotipo apparentemente non correlate.

Idrocefalia X-Linked: identificazione di una nuova mutazione del gene L1CAM in un feto

Microcephaly a clinical-genetic and neurologic approach

Duplicazione parziale Xq22.3-Xq25 in un soggetto di sesso femminile con anomalie fenotipiche

Diagnosis and follow-up of complex congenital malformations/mental retardation (MRA/MR)

Complex congenital malformations, associated in 30% of cases with mental retardation, recognize different etiologies: environmental causes, mendelian disease, chromosomal abnormalities, imprinted anomalies. Frequently complex congenital disorders are rare diseases. Rare diseases are infrequent pathological conditions (prevalence in the general population of less than 1/2.000 live births1), and often poorly understood. Because of their rarity these morbid conditions often either go undiagnosed or are diagnosed late with a negative impact for both the affected person and the family. The birth prevalence is high (2-4% of all births). The diagnosis is essential to program complex and integrated…

X-LINKED INTELLECTUAL DISABILITY

The intellectual disability is found in approximately 2-3% of the population in a mild-to-moderate form and 0.5-1% in a moderate-to-severe form. The mutations on the chromosome X are responsible for both syndromic and non-syndromic intellectual disability. In the syndromic forms behavioral disorders, autism and/or seizures are frequent.

14q13.1-21.1 deletion encompassing the HPE8 locus in an adolescent with intellectual disability and bilateral microphthalmia, but without holoprosencephaly

Interstitial deletions involving 14q13.1q21.1 are rare. In the literature at least 10 cases involving this region have been described and all patients showed a phenotype within the holoprosencephaly (HPE) spectrum. Previous studies suggested the HPE8 region as a candidate locus for HPE at 14q13. We report an adolescent with a 14q13.1q21.1 deletion encompassing the HPE8 region associated with intellectual disability (ID), bilateral microphthalmia, and coloboma, without cerebral anomalies typical of HPE. Except for ocular defects (i.e., microphthalmia, coloboma) consistent with HPE-type anomalies, the minor facial dysmorphia was not suggestive for HPE and the absence of cerebral anomalies sho…

Type and counter-type from specific chromosomal regions

Several studies have shown the importance of segmental deletions/duplications in the field of chromosome pathologies. Non allelic homologous recombination, NAHR, between chromosomes or sister chromatids, mediated by segmental duplications, is the foundation of frequent mechanisms for structural chromosome mutations such as micro-deletions, micro-duplications, translocations, inversions, and marker chromosomes. We analyzed three distinct genomic regions (22q11.2, 17p11.2, 16p11.2) and we discussed how the same chromosome region can be affected by deletion or by reciprocal duplication, respectively responsible for a syndrome or for a reciprocal counter-syndrome, with different phenotypic mani…

Marker cromosomico soprannumerario inv/dup 15 ed autismo

Copy number variations in the etiology of epilepsy

Epilepsy is one of the most common neurological disorders in humans with a prevalence of 1% and a lifetime incidence of 3%. Idiopathic epilepsies occur in the absence of identifiable causal factors, but recent evidences show the role of genetic factors in the developing of these disorders. In particular, several studies focused their attention on the role of copy number variations (CNVs) in the etiology of epilepsy. In recent years, many CNVs have been identified, like 15q11.2, 15q13.3 and 16p13.11 microdeletions, 22q11.2 microduplication and many others. Possible candidate genes included in these regions were also studied and they seem to be involved in neuronal transmission and ion transp…