code: public static boolean isOverlapping(Variant blockRecord, Variant.Builder variant) {
      return blockRecord.getStart() <= variant.getStart()
          && blockRecord.getEnd() >= variant.getStart() + 1;
    }
docs: Determine whether the first variant overlaps the second variant.
  
  This is particularly useful when determining whether a non-variant segment overlaps a variant.
  
  @param blockRecord
  @param variant
  @return true, if the first variant overlaps the second variant