You will be shown a question, followed by excerpts from biomedical research papers. Please answer the question based on the provided context. Do not include any text in your response other than the answer.

Question: How are deletion breakpoints defined?

Context: Molecular mapping of deletion breakpoints on chromosome 4 of Drosophila melanogaster.
In this study, we investigated the deletion breakpoints of the parkin mutations in 22 families with AR-JP and examined the possible association between these deletion events and meiotic recombinations. We identified 18 deletion breakpoints at the DNA nucleotide sequence level.
Hemizygotic deletions or duplications in the large Duchenne muscular dystrophy DMD gene responsible for Duchenne and Becker muscular dystrophies are routinely identified using multiple ligation probe amplification and array-based comparative genomic hybridization.
Commonly used methods for the detection of CNV breakpoints include long-range PCR and primer walking, their success being limited by the deletion size, GC content and presence of DNA repeats.
he hemizygous deletion of exons 45-50 in the DMD gene and the large autosomal heterozygous PARK2 deletion were used to demonstrate the workflow that relies on real-time quantitative PCR to narrow down the deletion region and Sanger sequencing for breakpoint confirmation.
Specifically, (AT)n, (GAA)n and (GAAA)n constitute the most frequent repeats at translocation breakpoints, whereas A-tracts occur preferentially at deletion breakpoints
Using this approach, we have efficiently defined the proximal and distal breakpoints in two cytogenetic cases, one duplication and one deletion, to within 5-20 kb. The results support the potential use of BAC-based PCR fragments to further improve the resolution of the microarray-CGH strategy by an order of magnitude.
The deletion breakpoints were defined by a combination of long polymerase chain reaction (PCR) amplifications, and conventional PCR and DNA sequencing.
In this investigation, polymerase chain reaction (PCR)-based techniques and sequencing were used to isolate the deletion breakpoints, utilizing the newly available dog genome sequence.
The deletion breakpoints were defined by a combination of long polymerase chain reaction (PCR) amplifications, and conventional PCR and DNA sequencing.
We used paralog-specific primers and long-range PCR to clone, sequence, and examine the distal deletion breakpoints from two patients with de novo deletions mapping to these distal LCRs.
To define the Thailand deletion breakpoints, we used polymerase chain reaction (PCR) to amplify the normal-sequence DNA fragments across the breakpoints.
Molecular mapping of deletion breakpoints on chromosome 4 of Drosophila melanogaster. We identified 18 deletion breakpoints at the DNA nucleotide sequence level.  Commonly used methods for the detection of CNV breakpoints include long-range PCR and primer walking, their success being limited by the deletion size, GC content and presence of DNA repeats. We identified 18 deletion breakpoints at the DNA nucleotide sequence level.  Molecular mapping of deletion breakpoints on chromosome 4 of Drosophila melanogaster. In this study, we investigated the deletion breakpoints of the parkin mutations in 22 families with AR-JP and examined the possible association between these deletion events and meiotic recombinations. he hemizygous deletion of exons 45-50 in the DMD gene and the large autosomal heterozygous PARK2 deletion were used to demonstrate the workflow that relies on real-time quantitative PCR to narrow down the deletion region and Sanger sequencing for breakpoint confirmation.  Specifically, (AT)n, (GAA)n and (GAAA)n constitute the most frequent repeats at translocation breakpoints, whereas A-tracts occur preferentially at deletion breakpoints Commonly used methods for the detection of CNV breakpoints include long-range PCR and primer walking, their success being limited by the deletion size, GC content and presence of DNA repeats. Commonly used methods for the detection of CNV breakpoints include long-range PCR and primer walking, their success being limited by the deletion size, GC content and presence of DNA repeats. A promising new workflow relies on real-time quantitative PCR to narrow down the deletion region and Sanger sequencing for breakpoint confirmation. Commonly used methods for the detection of CNV breakpoints include long-range PCR and primer walking, their success being limited by the deletion size, GC content and presence of DNA repeats.  We identified 18 deletion breakpoints at the DNA nucleotide sequence level. Specifically, (AT)n, (GAA)n and (GAAA)n constitute the most frequent repeats at translocation breakpoints, whereas A-tracts occur preferentially at deletion breakpoints Commonly used methods for the detection of CNV breakpoints include long-range PCR and primer walking, their success being limited by the deletion size, GC content and presence of DNA repeats. Molecular mapping of deletion breakpoints on chromosome 4 of Drosophila melanogaster.