Biotype Rh-negative is a Basque biotype. This type has inherited a Basque gene for blood type Rh-negative from ancient ancestors in the Pyrenees Mountains of France and Spain. Their ancestors adapted to their specific ecosystem over long periods of time in isolation, and modern Rh-negatives have inherited those adaptations.
You will find the chromosomes and genetic material in the nucleus of a cell. In prokaryotes, DNA floats in the cytoplasm in an area called the nucleoid. Chromosomes are not always visible. They usually sit around uncoiled and as loose strands called chromatin. When it is time for the cell to reproduce, they condense and wrap up very tightly. The tightly wound DNA is the chromosome. Chromosomes look kind of like long, limp, white hot dogs.
DNA is the heredity material of the cell. Some cells (bacterial cells) have one large circular DNA strand. In other organisms like us (aka eukaryotic cells) the dna for the cell is in several linear strands instead of one large circular piece of DNA. Each one of these strands of DNA is called a chromosome. The DNA of each chromosome is really tightly wound up around proteins called histones. Finally, a gene is a small segment of DNA, found in a small section of the chromosome (These can often be seen as dark bands in pictures of chromosomes). It is here, at the gene, that the DNA uncoils and opens up momentarily in order to have the gene 'read' and eventually copied into a protein (aka polypeptide).