The sequence below from BRCA2 exon 21 was obtained from a patient affected with breast cancer. What is the mutation? How would you describe it using HGVS guidelines (http://www.hgvs.org/)? How would you report the mutation?.

Figure.  Partial sequence traces for exon 21 of BRCA2 from (a) normal control and (b) affected patient. (c) Sequence for exon 21, nucleotides 8861-8982, accession no U43746, intronic sequence in lower case.