Genome mapping — A chromosome map that uses cloned and sequenced DNA fragments (e.g., restriction fragments, contigs, sequence-tagged sites) rather than classical genetic markers is known as what?

Introduction / Context:
Genome maps come in multiple types. Genetic (linkage) maps order markers based on recombination frequencies in crosses. Physical maps place DNA features according to actual base-pair distances along chromosomes using molecular tools such as restriction mapping, BAC contigs, and sequence assemblies. Understanding the distinction is vital for positional cloning and genome assembly.

Given Data / Assumptions:

• Question emphasizes cloned and sequenced DNA fragments.
• Focus is on absolute order and distances in base pairs, not recombination frequency.
• Terminology follows standard genomics usage.

Concept / Approach:
A physical map represents the literal arrangement of DNA sequences. Early physical maps used restriction fragment maps and overlapping clone contigs; modern approaches rely on long-read sequencing and scaffolding to create near-complete assemblies. Genetic maps complement physical maps but can differ due to recombination hot/cold spots.

Step-by-Step Solution:

Verification / Alternative check:
Human genome project milestones included both a high-resolution physical map of BAC contigs and genetic linkage maps; both were necessary but distinct.

Why Other Options Are Wrong:

Common Pitfalls:
Assuming higher recombination frequency equals larger physical distance; recombination landscapes vary significantly across genomes.

Final Answer:
A physical map.