Include Blank Value In Validation List

i have two sheets in workbook named as shtbiz,shtbiz1.

so column A of my shtbiz1 sheet i have 100 datas.the by using following code i can fill the datas of shtbiz1 in column A of shtbiz.

Dim strValItems
strValItems = ""
Set rngValList = ShtBiz1.Range("A6", Range("A10000").End(xlUp))
With ShtBiz.Range("A6:A10000")
. Validation.Delete
For Each rngValCell In rngValList
If Len(strValItems) > 0 Then strValItems = strValItems & ","
strValItems = strValItems & rngValCell.Value

Next
.Validation.Add xlValidateList, , , strValItems
End With

so my problem is i need to add blank value in the top of the list .ie first value should be blank then other values which read from shtbiz1 has to be followed.