wie viele gene hat der mensch — what symptoms are typical?

The question about the number of human genes is well-established: humans have approximately 20,000–25,000 protein-coding genes, plus thousands of non-coding RNA genes and regulatory elements. The exact count varies by database (e.g., Ensembl, GENCODE) and definition of 'gene'. The second part – 'what symptoms are typical?' – is ambiguous without context. If referring to genetic disorders, typical symptoms range widely: metabolic disturbances, developmental delays, increased cancer risk, etc. Direct-to-consumer tests like MyBody-X analyze specific variants (e.g., PCSK9 for cholesterol), but they do not diagnose clinical symptoms. Evidence for gene count is strong (human-strong); for symptoms in the context of consumer genetics, evidence is mixed – many associations come from GWAS or mechanistic studies, not clinical validation in a consumer setting. Important: genetic testing does not replace medical evaluation. Symptoms should always be assessed by a healthcare professional.