To paraphrase an old saying, gene changes should be weighed not counted. There are a plethora of types of gene changes, and they vary by orders of magnitude in their impact. In particular, which genes are affected has a huge impact. Some point mutations (change in a single or a few nucleotides) can be lethal. On the other hand there are trisomies where an ...
There are about 20,000 genes in the human genome. Here are the first 5 genes (following alphabetical order) on chromosome 1:
AADACL3: Arylacetamide deacetylase-like 3
AADACL4: Arylacetamide deacetylase-like 4
ACADM: acyl-Coenzyme A dehydrogenase, C-4 to C-12 straight chain
ACTL8: Actin-like 8
ADGRL2 (1p31.1): adhesion G protein-coupled receptor L2