Long fragment read techniques can be used to identify deletions and resolve base calls by utilizing shared labels (e.g., shared aliquots) of a read with any reads corresponding to heterozygous loci (hets) of a haplotype. For example, the linking of a locus to a haplotype of multiple hets can increase the reads available at the locus for determining a base call for a particular haplotype. For a hemizygous deletion, a region can be linked to one or more hets, and the labels for a particular haplotype can be used to identify which reads in the region correspond to which haplotype. In this manner, since the reads for a particular haplotype can be identified, a hemizygous deletion can be determined. Further, a phasing rate of pulses can be used to identify large deletions. A deletion can be identified with the phasing rate is sufficiently low, and other criteria can be used.