Comparative multiplex dosage analysis in spinocerebellar ataxia type 2 patients.
We developed a new application of comparative multiplex dosage analysis (CMDA) for evaluation of the ataxin 2 gene. Expansions of the triplet CAG can cause spinocerebellar ataxia type 2 (SCA2), a neurodegenerative disease with an autosomal-dominant mode of inheritance. Molecular diagnosis of SCA2 is routinely based on the use of conventional PCR to detect the CAG expansion. However, PCR does not amplify an allele with an expansion of many triplets (>80), which is typically found in infantile and juvenile forms of SCA2, thus leading to false negatives. We propose the analysis of the ATXN2 gene by CMDA to complement existing methods currently used for the detection of large expansions of the …
SPANX-B and SPANX-C (Xq27 region) gene dosage analysis in Down’s syndrome subjects with undescended testes
Down’s syndrome (DS) is one of the most common numer- ical chromosomal aberrations, usually caused by trisomy of chromosome 21, and is frequently complicated with congen- ital heart defects, duodenal obs truction and other conditions including undescended testis (UDT) (Fonkalsrud 1970). The incidence of undescended testes in DS was reported to be 6.52% (Chew and Hutson 2004) while the incidence of UDT in the first year is approximately 0.2%–0.8% in the nor- mal population (Benson et al . 1991; Ichiyanagi et al . 1998). Rapley et al . (2000) provided evidence for a testicular germ- cell tumours (TGCT) predisposition locus at Xq27; the au- thors obtained an hlod score of 4.7 from families wit…
Multiplex ligation-dependent probe amplification detection of an unknown large deletion of the CREB-binding protein gene in a patient with Rubinstein-Taybi syndrome
Rubinstein-Taybi syndrome is a rare autosomal dominant congenital disorder characterized by postnatal growth retardation, psychomotor developmental delay, skeletal anomalies, peculiar facial morphology, and tumorigenesis. Mutations in the gene encoding the cAMP response element-binding protein (CREB, also known as CREBBP or CBP) on chromosome 16p13.3 have been identified. In addition, some patients with low intelligence quotients and autistic features bear large deletions. Based on these observations, we used multiplex ligation-dependent probe amplification to search for large deletions affecting the CREBBP gene in a Rubinstein-Taybi syndrome patient. We identified a novel heterozygote dele…