Table 3. The four basic types of X chromosome attachments.

Reversed metacentric	C(1)RM	Telomere———–•———–Telomere
Tandem metacentric	C(1)TM	Telomere———–•Telomere———–
Reversed acrocentric	C(1)RA	Telomere———————-Telomere•
Tandem acrocentric	C(1)TA	Telomere———–Telomere———–•