Familial occurrence of Turner syndrome: casual event or increased risk?

Aim: The prevalence of Turner syndrome (TS) at birth has been estimated as approximately 1 in 2500 live female births. An increased risk of TS in subsequent pregnancies for couples who already have a daughter with TS has not been reported.

Methods: We reviewed the records of 140 patients to evaluate the presence of familial TS occurrence.

A 12Mb deletion at 7q33-q35 associated with autism spectrum disorders and primary amenorrhea.

An interstitial deletion of about 12Mb at 7q33-q36 was found in an adult female affected by autism and primary amenorrhea. Two genes, CNTNAP2 and NOBOX, both contained within the deletion region, have been recently associated with autism susceptibility and premature ovarian failure, respectively. Our findings reinforce the hypothesis that haploinsufficiency of both these genes is sufficient for autism development and occurrence of primary amenorrhea, confirming a previous case in which CNTNAP2 had been disrupted by a chromosome inversion and possibly enlarging the phenotype of ovarian function disturbances already demonstrated for NOBOX mutations.

13q Deletion and central nervous system anomalies: further insights from karyotype-phenotype analyses of 14 patients.

Background: Chromosome 13q deletion is associated with varying phenotypes, which seem to depend on the location of the deleted segment. Although various attempts have been made to link the 13q deletion intervals to distinct phenotypes, there is still no acknowledged consensus correlation between the monosomy of distinct 13q regions and specific clinical features.

Methods: 14 Italian patients carrying partial de novo 13q deletions were studied.

Screening of Nijmegen breakage syndrome 1 mutations in four unrelated families by polymerase chain reaction using sequence-specific primers.

Nijmegen breakage syndrome (NBS) is an autosomal recessive disorder characterized by a marked predisposition to lymphoreticular malignancies. The rarity of the disease and the presence, in several cases, of a mild clinical phenotype make diagnosis difficult. The underlying gene, NBS1, consists of 16 exons and encodes nibrin, a member of the hMRE11/hRAD50/hNBS1 protein complex.

Mild Nijmegen breakage syndrome phenotype due to alternative splicing.

Hypomorphic mutations of the NBS1 gene are responsible for Nijmegen breakage syndrome (NBS), characterized by microcephaly, chromosomal instability, radiosensitivity, immunodeficiency and high cancer predisposition. Over 90% of NBS patients are homozygous for the 657Delta5 mutation and are of Slavic origin; however, 10 further truncating mutations have been identified in patients of other ethnic origin. Partially functional proteins produced by alternative initiation of translation, and possibly diminishing the severity of the NBS phenotype, have been described for several NBS1 mutations.

XX sex reversal, palmoplantar keratoderma, and predisposition to squamous cell carcinoma: genetic analysis in one family.

We describe a large inbred Sicilian family that includes four 46, XX (SRY-) brothers. Palmoplantar hyperkeratosis (PPK) and an associated predisposition to squamous cell carcinoma (SCC) of the skin, segregates as a recessive trait within the family. Interestingly, all the PPK-affected members of the family are phenotypic males (46,XY or 46,XX) while seven XX sibs are healthy phenotypic females with no signs of PPK.

Chromosome 10p deletion in a patient with hypoparathyroidism, severe mental retardation, autism and basal ganglia calcifications.

Chromosome 10p terminal deletions have been associated with a DiGeorge like phenotype. Haploinsufficiency of the region 10p14-pter, results in hypoparathyroidism, sensorineural deafness, renal anomaly, that is the triad that features the HDR syndrome. Van Esch (2000) identified in a HDR patient, within a 200 kb critical region, the GATA3 gene, a transcription factor involved in the embryonic development of the parathyroids, auditory system and kidneys.

Growth hormone deficiency, anorectal agenesis, and brachycamptodactyly: a phenotype overlapping Stratton-Parker syndrome.

Stratton and Parker [1989] described a 17-month-old boy with the previously unreported combination of growth hormone (GH) deficiency, Wormian bones, mild developmental delay, brachycamptodactyly, heart defects, kidney hypoplasia, imperforate anus, bilateral cryptorchidism, and facial anomalies. A similar case was later reported by Gabrielli et al. [1994], who suggested the existence of a "Stratton-Parker syndrome.

Smith-Magenis syndrome and growth hormone deficiency.

Unlabelled: Smith-Magenis syndrome (SMS) is a multiple congenital anomaly/mental retardation syndrome including physical and neurobehavioural features. The disease is commonly associated with a ca. 3.

Chromosome instability and nibrin protein variants in NBS heterozygotes.

The frequency of spontaneous chromosome abnormalities in peripheral blood lymphocytes and the X-ray G2 sensitivity in lymphoblastoid cell lines (LCL) have been evaluated in heterozygous subjects from three unrelated Nijmegen Breakage Syndrome (NBS) families, characterised by different mutations in the NBS1 gene. In all the 13 NBS heterozygotes analysed, we found spontaneous chromosome instability consisting in chromosome and chromatid breakages and rearrangements, while radiosensitivity was similar to that of control LCLs in seven out of eight tested NBS heterozygotes. The densitometric analysis of nibrin by immunoblotting indicated only a slight reduction in some of the LCLs from NBS carriers, whereas the immunoprecipitation assay appears a more reliable tool to detect NBS carriers.

Interstitial deletion of chromosome 9, int del(9)(9q22.31-q31.2), including the genes causing multiple basal cell nevus syndrome and Robinow/brachydactyly 1 syndrome.

We report a child with a de novo interstitial deletion, 46,XY, int del(9)(9q22.31-q31.2).