Design, Construction and Validation of Targeted BAC Array-Based CGH Test for Detecting the Most Commons Chromosomal...

Area of Science:

• Genomics
• Medical Genetics
• Molecular Diagnostics

Background:

• Microdeletion and microduplication syndromes are significant causes of genetic disorders.
• Accurate detection of chromosomal abnormalities is crucial for clinical diagnosis.
• Existing methods may have limitations in resolution or coverage for specific genomic regions.

Purpose of the Study:

• To develop and validate a targeted BAC array, the GOLD (Gain or Loss Detection) Chip, for enhanced detection of genomic rearrangements.
• To assess the clinical diagnostic applicability of the GOLDChip for common microdeletion syndromes and aneuploidies.
• To improve the diagnostic yield for well-characterized human genomic disorders.

Main Methods:

• Design of a targeted array (GOLDChip) with 900 FISH-mapped BAC clones covering 66 specific genomic regions.
• Inclusion of a 10 Mb backbone for aneuploidy detection and enhanced resolution for telomeres and disease-associated regions.
• Analytical validation using retrospective analysis of 47 DNA samples from cytogenetically normal and abnormal cases, including various syndromes and trisomies.

Main Results:

• The GOLDChip successfully identified chromosomal rearrangements in all analyzed DNA samples.
• The array demonstrated capability in detecting specific microdeletion syndromes (e.g., Cri du Chat, Williams, Prader Willi/Angelman, Smith-Magenis, DiGeorge, Miller-Dieker).
• Detection of common aneuploidies, including trisomies 13, 18, and 21, was confirmed.

Conclusions:

• The GOLDChip is a valuable tool for the identification of common microdeletion syndromes.
• The targeted BAC array provides reliable detection of common aneuploidies.
• The GOLDChip shows significant potential for clinical diagnostic applications in genetic testing.