According to current researches，Single nucleotide variants（SNV，单核苷酸变异分析） and Insertion–deletion variants（indels） are easier to be interpreted（解释） than other types of variants（变异）.

A.The clinical diagnosis may or may not be specific
B.The inheritance mode is not clear for the isolated cases
C.The progression（进展） of condition can take several decades
D.Locus heterogeneity（位点差异性）

A.Chromosome banding
B.FISH
C.Mass spectrometry（MS）
D.Next Generation Sequencing（NGS-二代测序）