Table 3.

Included studies conducted in other monogenic conditions.

Author [ref.]	Study location	Disease state	Focus of study	Proband population	Included relatives	Main findings/conclusions
Stark et al. [19]	Australia	Rare monogenic disorders	• Clinical and cost impacts of genomic sequencing in infants with suspected monogenic disorders	• Paediatric (number not specified), mean age (range): 8 months (1 week–34 months)	• 88 first-degree relatives	Relatives: • 90% underwent genetic testing (total cost: AU $28,000) • 2 first-degree relatives changed medical management based on genetic test results (yearly costs: AU $146 and AU $329) • 16 couples accessed reproductive genetic services (total cost: AU $56,904.37)
Famula et al. [21]	United States	Fragile X syndrome	• Identification of affected child through newborn screening • Outcome of cascade genetic testing	• 1 child, aged 3 months	• 3 family members (mother and 2 siblings)	Relatives: • all 3 relatives found to have full FMR1 (fragile X-associated) variant
McClaren et al. [17]	Australia	CF	• Uptake of relative carrier testing and factors influencing uptake	• 30 children, ages not reported	• 225 relatives	Relatives: • 37% underwent carrier testing
Sorensen et al. [23]	United States	Fragile X syndrome	• Description of pilot project: newborn screening followed by cascade testing • Detailed description of 3 newborns identified as having Fragile X syndrome premutation	• 3,024 newborns screened; 14 positive • 3 newborns described in detail, aged 5 months, 5 months, and 6 months	• 44 relatives of variant-positive probands	Relatives: • 27/44 (61%) positive
Moriwaki et al. [32]	Japan	XP-A	• Experience of 1 centre with prenatal diagnosis of XP-A	• 12 children from 9 families, mean age (range): 3.83 (1–11) years	• 10 fetuses in utero	Fetuses: • 2/10 XP confirmed • 6/10 XP carriers • 2/10 unaffected
Sorensen et al. [22]	United States	Fragile X syndrome	• Description of fragile X syndrome sibship • Outcome of cascade genetic testing	• Brother and sister pair; brother was true proband, aged 9.75 years	First- and second-degree relatives (number not specified)	Relatives: • Parents both carriers • Third sibling unaffected • Maternal grandmothers obligate carriers
McClaren et al. [14]	Australia	CF	• Uptake of cascade genetic testing by non-parent adult relatives	• 30 children, ages not reported	• 59 parents • 716 non-parent first- and second-degree relatives	Parents: • 64.4% underwent genetic testing Non-parent relatives: • 11.5% underwent genetic testing • 2.7 relatives tested per child • Female relatives 1.61 times more likely than males to undergo cascade testing
Smith et al. [31]	Australia	SMA	• Carrier frequency of SMA in Australia	• Paediatric (number not specified), ages not reported	• 117 parents of affected children • 158 individuals with family history • 146 individuals without family history	• SMA carrier frequency ~1/49
Rudolph et al. [33]	Germany	X-linked ocular albinism	• Outcomes of genetic testing and clinical screening	• 1 male, aged 8 months	• 22 relatives	Family members: • 6 male relatives affected • 6 other relatives identified as obligate carriers

CF cystic fibrosis, SMA spinal muscular atrophy, XP-A xeroderma pigmentosum complementation group A.