A couple planning their family are aware that through the past three generations on the husband's side a substantial number of stillbirths have occurred and several malformed babies were born who died early in childhood. The wife has studied genetics and urges her husband to visit a genetic counseling clinic, where a complete karyotype-banding analysis is performed. Although the tests show that he has a normal complement of 46 chromosomes, banding analysis reveals that one member of the chromosome 1 pair (in group A) contains an inversion covering 70 percent of its length. The homolog of chromosome 1 and all other chromosomes show the normal banding sequence. Part A How would you explain the high incidence of past stillbirths?

The largest chromosome is chromosome 1. An issue in this chromosome generally results in serious outcomes in the resulting individual. In the genetic heterozygous state, a crossing over in the inversion loops of the male's chromosome 1 will result in the defected and unbalanced chromatids. These defects in chromosome 1 will most likely give rise to the malformed children and stillbirths.