BLOOM'S SYNDROME

BLM Sequencing

DNA ANALYSIS

Also see: 6012 - Bloom's Syndrome - Mutation Analysis


Bloom's syndrome is a rare autosomal recessive disease characterized by growth deficiency, unusual facies, immunodeficiency, male sterility/female subfertility and an increased risk of a broad spectrum of cancers that develop at a young age. Bloom's Syndrome is caused by inactivating mutations in both copies of the BLM gene, which is located on chromosome 15 at 15q26.1. One particular BLM gene mutation, corresponding to a 6-bp deletion and a 7-bp insertion at nucleotide position 2281, known as the BLM Ash mutation, is the common mutation in Bloom's Syndrome patients of Ashkenazi Jewish ancestry. BLM encodes the Bloom's syndrome protein, a DNA helicase of the highly conserved RecQ subfamily of helicases, a group of nuclear proteins important in the maintenance of genomic stability. Sequence analysis of the entire BLM gene associated with Bloom's Syndrome is available on a clinical basis at the Medical Genetics Laboratories at Baylor College of Medicine.

Reasons For Referral:

  • Confirmation of clinical diagnosis
  • Carrier testing of known familial mutations
  • Prenatal diagnosis (known familial mutations)

Testing Methodology:

PCR amplification of the exons contained in the BLM gene coding region will be performed on patient genomic DNA. Direct sequencing of amplification products is performed in both the forward and reverse directions using automated fluorescence dideoxy sequencing methods.

Sensitivity:

98% detection for Ashkenazi Jewish Bloom's syndrome patients

Specimen Requirements:

Require 14 mls of blood in EDTA tube. Consent form must accompany specimen.

Turnaround Time:

4 weeks

CPT Codes and Prices:

Index: 83891, 83898x29, 83894, 83904x58, 83909x58, 83912
KFM: 83891, 83898, 83894, 83904x2, 83909x2, 83912

Shipping Information


Forms:

 >> Gene Sequencing Requisition or DNA Requisition
 >>
Prenatal Requisition

Test Codes:

Index: 6535
KFM: 6536
Prenatal: 6537