CytoCell Prader-Willi/Angelman (SNRPN) FISH Probe

Product summary

Technology FISH
Application Cytogenetics & rare disease
Areas of interest Constitutional
Region 15q11.2
15qter
Label
Product Code LPU 005 (10 tests)
LPU 005-S (5 tests)
Regulatory Status In vitro diagnostic. This product is intended to be used on Carnoy’s solution (3:1 methanol/acetic acid) fixed peripheral blood samples.

Documentation

Chromomaps

15q11.2 (SNRPN)

FISH chromosome map showing a probe targeting a region associated with Prader-Willi and Angelman syndromes (SNRPN gene).

Overview

Probe specification

SNRPN, 15q11.2, Red
15qter, 15q26.3, Green

The Prader-Willi/Angelman (SNRPN) probe is 170kb, labelled in red and covers the whole SNRPN gene as well as entire imprinting centre. The 15qter subtelomere specific probe (clone 154P1), labelled in green, allows identification of chromosome 15 and acts as a control probe.

Probe information

Prader-Willi Syndrome (PWS) and Angelman Syndrome (AS) are distinct neurogenetic disorders caused by the loss of function of genes on chromosome 15 (bands 15q11-13), on either the paternally or maternally inherited chromosome, respectively¹.

In 70% of patients, a large interstitial deletion of 3-4Mb is observed^1,2. In around 3% of patients, an imprinting defect is observed, caused by either an epimutation or a microdeletion of the Imprinting Centre (IC)^1,3. Uniparental disomy, in which both chromosome 15s are inherited from the same parent, accounts for most of the remaining patients with PWS/AS¹.

The SNRPN gene is one of four imprinted loci that are expressed from the paternal chromosome 15 region (15q11-13) and maps to the minimally deleted region (MDR) involved in PWS⁵. Its chromosomal location and imprinting status suggest it plays a possible role in the aetiology of PWS⁴.

The imprinting centre (IC) maps to a 100kb region proximal to SNRPN. Parental deletions or mutations in the IC impair the imprinting process in 15q11-13 and cause one of two distinct diseases in their offspring^5,6. Most of the PWS imprinting deletions involve SNRPN and are approximately 200kb in size. The AS imprinting deletions are small (approximately 40kb), involve the BD3 region, and do not include SNRPN.

Fluorescence in situ hybridisation (FISH) microscope image of the CytoCell Prader-Willi/Angelman (SNRPN) probe.

What our customers say

I first came across CytoCell FISH probes in a previous lab I worked in and I was struck by the quality of the products. Since this time, I have been recommending and introducing CytoCell probes across all application areas — now they are the primary FISH probes used in our lab. They have an excellent range of products and their ready-to-use reagent format saves considerable time.